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Being an Invasive Volunteer
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Welcome to the
Arizona-Sonora Desert Museum’s
INVADERS OF THE SONORAN DESERT REGION
EARLY DETECTION AND REPORTING PROGRAM
Welcome to the Arizona-Sonora Desert Museum (ASDM) Invaders of the Sonoran Desert
Region volunteer citizen scientist team! You are part of an exciting new national program
titled, “Invaders: Citizen Scientists Combat Invasive Species,” developed by ASDM in
partnership with Sea Studios Foundation, National Geographic and Vulcan Productions. This
innovative initiative was launched with the April, 2005 premiere of National Geographic’s
Strange Days on Planet Earth TV series on PBS. The opening episode of this new series is
all about Invaders.
Invasive, non-native species – organisms that evolved in one area of the world and have
been introduced to and invaded other areas (invaders) – are becoming increasingly
worrisome. One reason behind the worry is that we, humans, are major intentional and/or
unwitting agents of transportation for these marauding plants and animals. How serious is
the problem? What do we stand to lose? As renowned biologist E. O. Wilson states, “On a
global basis…the two great destroyers of biodiversity are, first, habitat destruction and
second, invasion by exotic species.” These invasive species aggressively overtake or
displace native species, and their ecological and economic impacts can be enormous.
Experts estimate the annual cost of invasive species to the US economy alone is in the
billions.
Invaders: Citizen Scientists Combat Invasive Species is an innovative campaign whereby
volunteer “citizen scientists” are trained using a specially developed Invasive Species Early
Detection and Reporting Kit. The intent of this kit is to empower the public to become
involved as citizen scientists in order to more effectively slow the spread of harmful invasive
species and reduce their economic damages. With this kit, volunteers can help detect
invaders’ arrival and dispersal in their own local areas. You will be working in the INVADERS
of the Sonoran Desert Region program to help detect local invasives and enter the data into a
national database hosted by USGS through a local ASDM web-based data entry form.
Through partnerships, the data you collect will be shared with managers on the ground for
use in invasive species control and management.
You will be learning to identify the invasive, non-native species that are the focus of this
program as well as many other species, to use GPS units, and to enter your data through the
internet. The following nine species are the initial focus of the Invaders of the Sonoran
Desert Region program:
Buffelgrass (Pennisetum ciliare)
Fountaingrass (Pennisetum setaceum)
Natalgrass (Melinis replens)
Sahara mustard (Brassica tournefortii)
Tamarisk (saltcedar) (Tamarix chinensis)
Athel tree (Tamarix aphylla)
Onionweed (Asphodelus fistulosus)
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Red imported fire ants (Solenopsis invicta)
Argentine cactus moth (Cactoblastis cactorum)
Your participation in this initiative will benefit the Sonoran Desert Region and will help us
work towards the goal of mapping invasive species nationwide. Volunteers in other parts of
the country are working in their local areas to accomplish the same task. Our data are
pooled together to create national maps that are used by local, state, regional, and federal
agencies and organizations to address the invasive species issue throughout the country.
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Being an Invaders Volunteer
We hope you will find volunteering in the Invaders Program an opportunity to learn as
much as possible about the Sonoran Desert Region and the Museum’s efforts to work
toward its conservation through citizen science and public education on invasive, nonnative species. We have goals for the outcomes of our program efforts as well as goals
for your own development as volunteers. We will measure the former in an evaluation
process throughout the program. To measure the latter, we have established a series of
certification benchmarks that you will be able to follow as you progress through your
training and subsequent fieldwork.
Goals of the Desert Museum’s Invaders Program

Develop a baseline map of the scope of our target invasive species in
our region.

Refine methods and materials for data collection and reporting online.

Support the efforts of our agency and organization partners.

Continue developing partnerships with regional resource management agencies
to guide us toward sites where we can focus our early detection and reporting
efforts.

Provide information to these partners that helps lead to the control and/or
eradication of invasive species where possible, and through these connections,
provide our volunteers an opportunity to help in these eradication efforts.
We value your contribution and welcome any insights you might have about how we might
improve in these efforts. Please see Invaders Program coordinators’ contact information
at the end of this section.
Invaders Volunteer Certification Benchmarks
As volunteer citizen scientists in the Invaders Program, we will have the opportunity to
measure your training and volunteer accomplishments against a series of certification
benchmarks. The levels of certification and requirements for each are:
1. Apprentice: Has completed the formal lab and field training at ASDM and is ready to
start data collection and reporting.
2. Intermediate: Reaches 50 hours of time working as an Invaders volunteer (including
training hours).
3. Expert: Has submitted five species-specific identification photos that are verified as
positive. Will no longer need to send an identification photo for that species with
subsequent data reports.
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Beyond the Invaders Program
Finally, we hope that you will share what you learn with friends, family, and neighbors and
take your interest to new levels. For those whose interest extends beyond early detection
and reporting, we will continue to form partnerships with institutions and agencies that are
doing eradication projects and hope to provide opportunities whereby Invaders volunteers
may assist in the eradication of some of the species we track.
Other Invasive Species Volunteer Opportunities
The Sonoran Desert Weedwackers have been eradicating buffelgrass and fountaingrass
in Pima County's Tucson Mountain Park since 2000. To date they have removed over
57,000 pounds of these invaders! They meet every second Friday and third Saturday of
each month. For more information check their website at
http://aznps.org/html/exotics_weedwackers.html.
Invaders Program Contact Information
Tani Hubbard
Invaders Program Coordinator
Arizona-Sonora Desert Museum
2021 N. Kinney Rd.
Tucson, AZ 85743
(520) 883-1380 ext. 133
thubbard@desertmuseum.org
Yajaira Gray
Invaders Program Volunteer Coordinator
Arizona-Sonora Desert Museum
2021 N. Kinney Rd.
Tucson, AZ 85743
(520) 883-3018
ygray@desertmuseum.org
See the handout with contact information for your fellow Invaders volunteers.
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INVADERS Volunteer Position Description
Position Title and Department: Invasive Species Field Researcher, Center for Sonoran
Desert Studies.
Reports to (name & Title): Yajaira Gray, INVADERS Volunteer Coordinator
Tani Hubbard, INVADERS Program Manager
Overview of position: Volunteers will conduct surveys in the field to look for invasive species.
They will be trained in the identification and reporting of these species. Field surveys will be
conducted throughout Arizona.
Primary Specific Tasks:
1. Search for and record data on invasive species around the state.
2. Use GPS units, digital cameras, and handheld PCs to collect data. Upload data on
Museum website.
3. Function as a “team leader” to train and direct future volunteers in field surveys of
invasive species.
Day(s) of week volunteer(s) work in this position: 2 days/month (8-10 hour days including
travel time and fieldwork) with opportunities for additional fieldwork as available.
Hours: Approximately 20 hrs./month
Duration (specify period or minimum # of months): On-going.
Number of individuals in this position: 20
Qualifications:
Physical requirements: Hiking skills, field-worthiness, ability to walk on uneven terrain
and work in all weather conditions. Ability to handle all situations in the field, including
map reading, trail-finding, first-aid situations, etc.
Skills/knowledge required: Ability to use (or be willing to be trained to use) digital
cameras, GPS units, handheld PC, and online data entry system.
Background/experience desired: Preferred background in natural history with an
emphasis in plant/animal identification. Familiarity with Sonoran Desert ecosystems
helpful.
Other Requirements: Availability for training and work projects on weekdays. Ability to
provide own transportation to field sites.
Benefits to the volunteer: Contribute to a nationwide citizen science initiative monitoring and
preventing the spread of invasive exotic species.
Name(s) of incumbent volunteer(s): None.
Drafted by: Robin Kropp and Tani Hubbard
updated: 12-06-06
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Invasive Species
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INVASIVE SPECIES
What is an invasive species?
An invasive species is non-native to the ecosystem in consideration and causes or is likely to
cause economic or environmental harm or harm to human health.
Sometimes you will see invasive species referred to as exotic, alien, or non-indigenous
species. The problem with these names is that they only refer to the non-native part of the
definition above. Many exotic or alien species do not cause harm to our economy, our
environment, or our health. In fact, the vast majority of “introduced” species do not survive
and only about 15% of those that do go on to become “invasive” or harmful.
An invasive species grows/reproduces and spreads rapidly, establishes over large areas, and
persists. Species that become invasive succeed due to favorable environmental conditions
and lack of natural predators, competitors and diseases that normally regulate their
populations.
Plants and animals have always moved around
Plants and animals have been moving from one place to another for many millennia. These
movements have been relatively slow, allowing for life forms to adapt to changes in habitat
and species interactions. Humans have always been agents of dispersal for plants and
animals either accidentally or intentionally. However, as humans began exploring the planet
on a larger scale, rates of introductions of species to new areas accelerated. Now with our
global economy and advanced technologies, these rates have reached a level never before
seen in ecological history.
How did invasive species reach the Southwest?
For more than 2,000 years, Native Americans moved plants and animals all over the
Southwest. Starting in the 1500’s, the number of new exotic species as well as the speed at
which they moved increased. The Spanish brought exotic agricultural crops and domestic
animals from other parts of the world to the Southwest during the Spanish conquest. The
new species introduced to the Southwest between 1500 and 1900 were accompanied by
changes in physical conditions in the landscape that accelerated the naturalization of these
exotics. At the same time, native species were declining. Dams and grazing significantly
contributed to the spread of exotic species. The arrival of the railroad resulted in another
increase in invasive species. With the development of roads, airlines, and global commerce,
species can now travel from one corner of the world to the Southwest in a matter of hours.
What is an introduction?
When a species ends up in a new ecosystem, it is considered “introduced.” Species do
naturally change their ranges slowly over time, but it is not these “natural” events that we are
concerned with. Most of the introductions that result in invasive species are human caused.
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In some cases, we deliberately introduce species. Examples of this include garden
ornamentals, range forage plants for cattle, animals and insects used to control other
organisms (particularly in agriculture), and plants used for erosion control and habitat
enhancement for wildlife.
Other species are introduced accidentally on imported nursery stock, fruits, and vegetables,
in ship ballast waters, on vehicles, in packing materials and shipping containers, through
human-built canals, and through human travel.
How does a species become invasive?
It is not enough for a species to be able to exist in its new environment, although a close
match between environmental conditions in the species' home environment and the
environment to which it is introduced is fundamental to its survival there. Beyond this, the
organism must be able to establish a viable and growing population. To do so, the new
species must be capable of outcompeting and/or displacing native organisms. Lack of
natural controls in the new environment is also a factor in the establishment of invasive
species. Without the diseases, parasites, and predators that regulated the invader’s
population in its homeland, it can spread rapidly.
Native species may also lack adaptations that allow them to resist competition from or
predation by invasive species. If the invasion (particularly with plant species) is coupled with
other disturbances to the new ecosystem (e.g., earth moving, plowing, fire, livestock grazing,
changes to surface and groundwater hydrology), native populations may be weakened from
the start and the ecosystem rendered more susceptible to an invasion..
Why do we care?
Invasive species are a form of biological pollution. Invasive species decrease biodiversity by
threatening the survival of native plants and animals. They interfere with ecosystem function
by changing important processes like fire, nutrient flow, and flooding. Invasive species
hybridize with native species resulting in negative genetic impacts. As renowned biologist E.
O. Wilson states, “On a global basis…the two great destroyers of biodiversity are, first,
habitat destruction and second, invasion by exotic species.”
Invasive species also have economic consequences and can endanger human health.
Invasive species contaminate agricultural seed crops and reduce their value, pose health
threats to livestock, and necessitate costly repairs to harvesting machinery. Invasive insects
can harm crop plants and reduce their productivity, contaminate harvest surpluses, and act
as vectors of disease among livestock or in human populations. Invasive species can also
destroy electrical equipment, homes, and buildings. Control of these organisms chemically,
biologically, and mechanically exacts great expenditures of time and money in addition to the
losses mentioned above. In the United States alone, these expenses may total many tens of
billion (the latest National Geographic article on Invaders estimates the cost at $140 billion)
dollars annually.
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WHAT CAN YOU DO TO STOP THE SPREAD OF INVASIVE SPECIES?
VOLUNTEER
You have already taken the first step to do all you can to stop the spread. Becoming a
volunteer in the INVADERS of the Sonoran Desert Region program is a great way to help
invasive plant managers and eradication groups to successfully prevent and control
invasions. You are also preparing yourself to be an educator of others in our community and
beyond.
You may also want to join an eradication program in our area. Links to some of these
programs will be available on the ASDM INVADERS web page at
www.desertmuseum.org/invaders.
EDUCATE YOURSELF AND OTHERS
You will learn the basics of invasive species threats and issues during your citizen scientist
training. There are many other sources of information available to you both in this handbook
and on the ASDM INVADERS website. Take this opportunity to expand your knowledge and
share it with your family, friends, and others in the community. If you come upon information
sources that you think would benefit other volunteers, please let us know so we can share
that information. We are relying on you as a citizen scientist to not only collect scientific data,
but to actively participate in our invasive species community awareness campaign.
DO NOT BE A VEHICLE OF DISPERSION
Most invasive species are introduced by humans accidentally. Learn how to prevent carrying
invasive species on your boats, cars, bicycles, motorcycles, and socks and hiking boots. You
can visit the following websites for more information on how to prevent the spread of
invasives.
Union of Concerned Scientists tips for preventing species invasions (We have included
this information in the following pages as well):
http://www.ucsusa.org/global_environment/invasive_species/page.cfm?pageID=390


Habitatitude – an initiative to prevent the release of unwanted fish and aquatic plants.
www.habitattitude.net
GARDEN WISELY
Avoid plants that self seed and show up outside of your garden. Do not use weedy
volunteers from parks and abandoned lots. Most non-native species are okay; the invasive
species are the ones to avoid. However, planting a native species garden can be very
rewarding. There are many resources to help with creating low-maintenance and colorful
native plant gardens that attract birds and wildlife.
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Invasive Species in the
Sonoran Desert Region
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INVASIVE SPECIES IN THE SONORAN DESERT REGION
Invasive species are altering the ecosystems of the Sonoran Desert Region.
Native plants have been displaced resulting in radically different habitats and
food for wildlife. Species like red brome and buffelgrass have become dense
enough in many areas to carry fire in the late spring and early summer. Sonoran
Desert plants such as saguaros, palo verdes and many others are not fireadapted and do not survive these fires.
The number of non-native species tends to be lowest in natural areas of the
Sonoran Desert and highest in the most disturbed and degraded habitats.
However, species that are unusually aggressive and well adapted do invade
natural areas. In the mid 1900’s, there were approximately 146 non-native plant
species (5.7% of the total flora) in the Sonoran Desert. Now non-natives
comprise nearly 10% of the Sonoran Desert flora overall. In highly disturbed
areas, the majority of species are frequently non-native invasives. These
numbers continue to increase.
It is crucial that we monitor, control, and eradicate invasive species that are
already here. We must also consider the various vectors of dispersal for invasive
species that have not yet arrived in Arizona, but are likely to be here in the near
future. Early detection and reporting is vital to prevent the spread of existing
invasives and keep other invasives from arriving and establishing. This is the
premise of the INVADERS of the Sonoran Desert Region program at the
Arizona-Sonora Desert Museum.
We have chosen nine invasive species to initiate the INVADERS program.
Seven of these species are invasive plants and two are animal species. The two
animal species are not yet in Arizona, but their arrival could be devastating to our
state. The nine species are:
Buffelgrass -Pennisetum ciliare
Fountaingrass - Pennisetum setaceum
Natalgrass - Melinis repens
Sahara mustard - Brassica tournefortii
Tamarisk (saltcedar) - Tamarix chinensis
Athel tree - Tamarix aphylla
Onionweed – Asphodelus fistulosus
Red imported fire ant - Solenopsis invicta
Argentine cactus moth - Cactoblastis cactorum
Information on each of these species including their identification, impact, history,
and distribution are included in the following pages of this handbook. This
information is also available on the ASDM website at
www.desertmuseum.org/invaders.
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BUFFELGRASS (PENNISETUM CILIARE)
What is it?
Buffelgrass is a shrubby grass to 1.5 feet tall and 3 feet wide. It looks like a
bunchgrass when small (either a seedling or recently burned, grazed, or cut). Older
plants branch profusely and densely at nodes, giving mature plants a messy
appearance. These nodal branches produce new leaves and flower spikes very
quickly after light rains, making buffelgrass an extremely prolific seed producer.
Some native grasses such as Arizona cottontop (Digitaria californica) branch sparsely
and do not appear shrubby. Bush muhly (Muhlenbergia porteri) is a true denselybranched shrub; it differs from buffelgrass in its very delicate texture.
An entire mature plant.
A single basal stem teased out, showing the
profuse branching above ground.
Inflorescences are 1.5 to 5 inches long, fat brown to purplish when fresh or
occasionally straw-colored. The spikes are crowded with dense bristly fruit which are
actually burs without hardened spines. (For this reason buffelgrass is sometimes
included in the genus Cenchrus, the burgrasses.) This is primarily a warm-season
grass, but below 3000 feet in our region it can grow and flower after almost any rain.
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The individual units visible in these
buffelgrass inflorescences are
basically soft burs.
The most similar native grass is plains
bristlegrass (Setaria macrostachya). The
individual seeds are clearly visible.
Why is it a Threat?
Buffelgrass grows densely and crowds out native plants of similar size. Competition
for water can weaken and kill larger desert plants. Dense roots and ground shading
prevent germination of seeds. It appears that buffelgrass can kill most native plants
by these means alone.
Tumamoc Hill in Tucson, home of the University of Arizona's historic Desert
Laboratory visible at left, has been overrun by buffelgrass in the last two decades. It
has not burned, but native plants are declining and dying from lack of water. Photos:
Travis Bean
[Red brome (Bromus rubens) is another invasive grass that has covered huge areas
of lower bajadas in the upper Sonoran Desert. This annual grass has caused serious
damage in the past several decades. It grows densely only in wetter years and
produces relatively mild fires, so fires are infrequent and don't completely kill native
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communities in one episode. Nonetheless conversion is progressing where it has
invaded.]
Buffelgrass is a very drought-tolerant perennial, so it can remain dense and even
spread in dry years. It is present to burn year round and supports hotter fires than
those of red brome. The Sonoran Desert evolved without fire as an ecological factor
and most of its plants cannot tolerate it. A single buffelgrass fire kills nearly all native
plants in its path. The buffelgrass invasion is now destroying steep hillsides
compared to red brome's flatter terrain, and is rapidly converting formerly rich
biological communities into monocultural wastelands.
A "natural" roadside with native
vegetation. AZ Hwy 85 in Organ Pipe
Cactus National Monument, where
buffelgrass is controlled.
Buffelgrass resprouts vigorously after
fires, but most native desert plants are
killed. Near Caborca, Sonora.
The shoulders of this road near Saric,
Sonora are almost 100% buffelgrass, a
common result where it isn't controlled.
Buffelgrass is abundant in the adjacent hills,
but heavy grazing keeps it from reaching
burnable density.
This hillside near Caborca, Sonora recently
burned, killing nearly all of the native
plants. Only charred skeletons of teddy bear
cholla (Cylindropuntia bigelovii) and a palo
verde (Parkinsonia microphylla) are visible.
The rich Arizona Upland vegetation that
once grew here can be seen in the distance.
There is growing evidence that buffelgrass depletes soil fertility in a decade or so. It
then dies and leaves behind a sterile wasteland. No one knows how much time will
be needed to restore such ruined land.
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Distribution
Native to the Old World where it is widespread in Africa, the Middle East, Indonesia
and nearby islands, and tropical Asia. Introduced to Australia and the New World.
In the Sonoran Desert Region buffelgrass is common in southern Arizona and most
of Sonora.
Habitat
There are two seemingly unrelated habitats in the Sonoran Desert. In valleys and
lower slopes buffelgrass invades disturbed areas such as roadsides and cleared or
grazed fields. It Arizona it is spreading very rapidly along medians and shoulders of
major highways and more slowly on smaller roads. In northern Sonora it has been
present longer, and it dominates long stretches of smaller highways. From the town
of Imuris, Sonora buffelgrass extends in a continuous ribbon along highway 15 all
the way to Sinaloa, interrupted only by a few cities.
A typical roadside habitat for buffelgrass
(under the stopsign). The larger grasses
are the related fountaingrass (Pennisetum
setaceum), which is also a serious invasive
threat.
This cleared field is nearly pure
buffelgrass. It has not dominated the
surrounding flats which have not been
cleared of vegetation.
Its other habitat is steep rocky hillsides, mostly east- and south-facing slopes. It is
most abundant on debris cones near the angle of repose. These steepest slopes may
be the best establishment sites from which it will eventually spread. Some less steep
hillsides are completely covered with buffelgrass, so the invasion may still be in its
early stages. It occurs from near sea level to 4150 feet elevation.
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Buffelgrass being censused on a
hillside near Magdalena, Sonora.
Most of the herbaceous plants have
disappeared.
A steep rocky hillside in the Pan Quemado Mts,
Ironwood Forest National Monument. Several patches of
buffelgrass are visible.
History
Buffelgrass was introduced to the United States about in the1930s as livestock
forage. It was in planting trials at the Soil Conservation Service nursery in Tucson
from 1938 to 1952. Several experimental plantings were done beginning in 1941 at
Aguila near Phoenix. Most did not do well. (Another planting in Avra Valley west of
Tucson in the early 1980s also died out where it was planted on flat ground.)
Records of collections in natural habitat were sparse until about 1980 when it began
a rapid expansion. One example is Organ Pipe Cactus National Monument, where
buffelgrass was rare before 1984 (Felger 1990). By 1994 it had occupied 20-25
square miles and was expanding rapidly. Few people other than botanists noticed it
in Arizona before 1990. Today it is difficult not to see it in the southern half of the
state.
A survey of roads done by the Desert Museum in 2004 revealed the full extent of the
buffelgrass invasion of Arizona and northern Sonora (map below).
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Buffelgrass distribution along roads in
Arizona and northern Sonora. Red
symbols in both maps denote areas
where buffelgrass is the dominant plant
and dense enough to burn.
Buffelgrass distribution in the Tucson
vicinity. The survey was not completed
within the urbanized zone; buffelgrass is
present here in nearly every vacant lot
and unpaved road shoulder.
What can be Done?
Buffelgrass can be controlled by manual pulling and herbicides. Organ Pipe Cactus
National Monument nearly eradicated patches covering ca. 25 square miles in three
years of intensive manual labor. After the initial control only minor efforts have been
required to destroy new infestations (though searching the huge park takes a great
deal of time). Volunteer groups such as Sonoran Desert Weedwackers are active in
controlling it in other areas such as Tucson Mountains Pima County Park.
The highest priority should probably be to control buffelgrass on roads outside of
urban zones, because these are the seed sources for invasion of natural habitats.
Second priority should go to the most valuable habitats such as parks.
In the long run we may need biological control. This will be a controversial issue
because buffelgrass is still valued as livestock forage. To this issue, it must be
publicized that buffelgrass is not nearly as economically viable as first thought.
Research in Africa, Australia, South America, Texas, and Sonora reveal that the
average useful life of a buffelgrass pasture is only 10-12 years. Under exceptional
management productive pastures have lasted only 15 or 16 years (Ibarra 1999).
Buffelgrass impoverishes the soil and evenually dies, leaving behind a sterile
wasteland that requires expensive efforts to restore productivity.
The public and land management agencies must be educated to recognize
Buffelgrass for the threat that it is. The state of Arizona declared it to be a noxious
weed in March 2005. On the other hand, at least one branch of the federal
government is breeding buffelgrass to develop more cold-hardy varieties.
Other common names: African foxtail grass, anjan grass, syn. Cenchrus ciliaris.
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References
Tellman, Barbara (ed.). 2002. Invasive Exotic Species in the Sonoran Desert Region.
University of Arizona Press.
Ibarra F., Fernando. 1999. Lo mejor del dia del ganadero. Summary of oral
presentation on website.
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FOUNTAINGRASS (PENNISETUM SETACEUM)
What is it?
Fountaingrass is an attractive, robust clumping grass
that grows up to 3 ft tall and wide. Its long, wiry leaves
are 11 to 30 in long from the base and form dense, light
green clumps in summer. Together the old whitish and
the new purplish inflorescences form a halo above the
green leafy core. The cylindrical inflorescences are thick,
4 to 14 in long, round in cross-section, pink, or purplish
during colder weather, and dry white. Soft silky hairs to
over an inch long surround the fruits. This grass is most
vigorous in the warm season (July-September), but also
flowers most of the year below 3000 feet in our region.
It appears to be somewhat more cold tolerant than
buffelgrass (Pennisetum ciliare) as it reaches 4800 feet
elevation in the Santa Catalina Mountains (650 feet
higher than buffelgrass).
Photo: Mark Dimmitt
Buffelgrass is another introduced African grass in the genus Pennisetum, which is
also a serious invasive species in the Sonoran Desert Region. It differs from
fountaingrass in its smaller size (1 to 1.5 ft tall), branched stems, broad leaves and
shorter (1.5 to 5 in long) fat, brown to purplish cylindrical inflorescences growing
from nodes along the stems. Above 4000 feet, bullgrass (Muhlenbergia emersleyi) is
a 3 ft tall, clumping native species that resembles fountaingrass. Its numerous small
seeds with long (0.5 in) purplish bristles form loose, flattened, nodding banners that
are unlike the cylindrical inflorescences of fountaingrass.
Photos: Mark Dimmitt
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Why is it a Threat?
Fountaingrass is a large grass that produces lots of seeds that can spread rapidly
spreads from cultivation into nearby disturbed areas, and eventually into natural
habitats. It often forms dense stands and aggressively competes with native species,
especially perennial grasses and seasonal annuals, for space, water, and nutrients.
Fountaingrass provides lots of fuel, and is well adapted to fire. In Hawaii ,
fountaingrass fires are a serious threat to the native species. After burns, it regrows
rapidly from extensive roots. In contrast, fire is not an ecological process in the
Sonoran Desert or tropical communities to the south, and native trees, shrubs, and
succulents are decimated by fire. In the Arizona Upland, grasses often dominate
roadsides and fires are more frequent than in undisturbed habitats. Grasses that
commonly occur with fountaingrass on roadsides include the native cane beardgrass
(Bothriochloa barbinodis), plains bristlegrass (Setaria macrostachya), purple
threeawn (Aristida purpurea) , spike pappusgrass (Pappophorum vaginatum),
tanglehead (Heteropogon contortus) , the non-native barley (Hordeum murinum) ,
Bermuda grass (Cynodon dactylon) , Lehmann lovegrass (Eragrostis lehmanniana),
Natalgrass (Melinis repens), red brome (Bromus rubens), and wild oats (Avena
fatua).
Threats from fountaingrass fires are most serious in natural riparian habitats in
scenic mountain canyons. In the Tucson area, it has invaded the rocky canyons in
Finger Rock, Pima, Sabino, and other Canyons in the Santa Catalina Mountains and
King Canyon in the Tucson Mountains . Fountaingrass is less of a threat in desert
grassland or chaparral above 3500 feet where fire is a natural process.
It has been declared as a state noxious weed by Hawaii and Nevada .
Distribution
Fountaingrass is native to North Africa and the Middle East . It has been widely
cultivated as an ornamental around the world and often escapes into natural
habitats. In the United States, it is common in southern Arizona, southern California,
southern Nevada, southwestern Utah, and Hawaii . It has also been found in Florida,
Louisiana, Tennessee, Oregon, Colorado, and Texas .
In Arizona it is widespread in the Phoenix, Tucson, Ajo, and Gila Bend areas in
Maricopa and Pima counties. It is also common along the Colorado River from Lake
Mead to Parker in Mohave and La Paz counties. A few plants have been found in
Cochise, Gila, Pinal, Santa Cruz , and Yavapai counties. In the Mexican portion of the
Sonoran Desert Region, it is only beginning to escape cultivation in Alamos, Kino
Bay, and Magdalena (Sonora), near Ensenada (Baja California), and Mulegé (Baja
California Sur).
21
Habitat
Fountaingrass mostly occurs on disturbed
roadsides, rocky outcrops, canyons, and
cliffs from 2000 to 3500 feet in the
Sonoran Desert Region in Arizona . It is
most common in riparian habitats within
paloverde-saguaro desertscrub in the
Arizona Upland Sonoran Desert . It is less
common in the Lower Colorado River
Valley desertscrub down to about 985
feet, and in chaparral, desert grassland,
and oak woodland up to 4800 feet. On the
Fountaingrass invading a suburban
north side of Tucson, it replaces
roadside. Photo: Mark Dimmitt
buffelgrass on roadsides and rocky road
cuts.
It is also common in another riparian habitat on flood lines and rocky shores of
reservoirs and rivers in low-elevation (400 to 1200 feet) Mohave and Sonoran
desertscrub. It is common from Lake Mead to Parker along the Colorado River in
some very hot, dry areas.
History
Although fountaingrass was reported in Hawaii as early as 1914, it was first collected
on roadsides in Arizona in the Santa Catalina Mountains (4500 ft elevation) and in
Ajo in 1940. It was used in urban landscapes in Tucson as early as 1940, and
cultivated in the Soil Conservation Nursery (now National Resource Conservation
Service) in 1941. It was well established in the Santa Catalina Mountains by the
1940's and the Phoenix area by 1962. Later specimens were collected in nowprotected natural areas in the Tucson area including Tumamoc Hill (1968), the
Arizona-Sonora Desert Museum (1966), and King Canyon (1988) in the Tucson
Mountains, and Sabino Canyon (1974) in the Santa Catalina Mountains. Like
buffelgrass, it has expanded dramatically in many areas since 1990.
What can be Done?
Poorly-maintained nurseries can be
sources of new invasive weeds.
Fountaingrass in this nursery is in seed
and can soon invade surrounding land.
Fountaingrass can be controlled by
physically removing the entire plant,
including the seed-bearing inflorescences.
Seedlings and small plants can easily be
pulled by hand. Iron digging bars or
shovels will help extract larger plants. It
may be necessary to return to controlled
areas for several years to remove
seedlings. Chemical treatments with
systemic herbicides may be needed to
control large infestations. Herbicides have
been sprayed from boats to control
fountaingrass along rocky shorelines of
Colorado River reservoirs.
There are alternatives for fountaingrass in
urban landscapes. Bronzeleaf
fountaingrass (var. cupreum) is a
22
genetically-modified sterile cultivar that can be planted instead of the normal plants.
Native grasses that resemble fountaingrass but are not invasive include bullgrass
and deergrass (Muhlenbergia rigens). Beargrass (Nolina microcarpa) and desert
spoon (or sotol, Dasylirion wheeleri) are native succulents that grow in large clumps
that are attractive in desert gardens and road medians.
Links
California Exotic Pest Plant Council:
http://ucce.ucdavis.edu/files/filelibrary/5319/17411.pdf
Pima County Exotic Species Council: www.co.pima.az.us/cmo/sdcp/
National Resource Conservation Service, National Plant Data Center , USDA. 2004.
The PLANTS Database, Version 3.5:
http://plants.usda.gov/cgi_bin/plant_profile.cgi?symbol=PESE3
Plant Conservation Alliance, Alien Plant Working Group:
www.nps.gov/plants/alien/fact/pesel.htm
References
Tellman, Barbara (ed.) 2002. Invasive Exotic Species in the Sonoran Desert .
University of Arizona Press.
23
NATALGRASS (MELINIS REPENS)
What is it?
Natalgrass (synonym Rhynchelytrum roseum) is an erect grass to 28 in tall that has
attractive long reddish or pink silky hairs on the triangular fruit at maturity, fading to
silvery white with age. In the northern part of its geographic range, it is short-lived
perennial or annual, but becomes stouter in warmer areas to the south. The
branched inflorescences are open (2-3 in wide) and fluffy. The leaves are narrow and
flat (3-8 in long) from unbranched stems. It can flower throughout the year under
favorable temperature and moisture conditions but is limited by hard freezes.
Photo: T.R. Van Devender
Photo: Mark Dimmitt
Bush muhly (Muhlenbergia porter) is a native species with pink inflorescences but
differs from Natalgrass in its sprawling growth habit and tiny pink seeds in nebulous
clusters growing from stem nodes. Arizona cottontop (Digitaria californica) also has
white silvery hairs but the fruit are flattened, oval, and in slender spikes rather than
open panicles.
Why is it a Threat?
In most areas in the Tucson vicinity,
Natalgrass mainly occurs on roadsides
and does not present a serious threat to
natural ecosystems. But in eastern and
north-central Sonora it left the roadsides
and invaded natural grassland habitats
beginning about 1990. As with Lehmann
lovegrass (Eragrostis lehmanniana),
weeping lovegrass (E. curvula), King
Ranch bluestem (Bothriochloa
ischaemum), and other non-native forage
grasses in Arizona, the introduction of
Natalgrass has recently taken over this
Natalgrass results in changes in the
hillside near Yécora, Sonora. Photo: T.R. composition and structure of desert
Van Devender
grassland, but not conversion to
desertscrub or some other type of
vegetation. In contrast to buffelgrass (Pennisetum ciliare), it does not appear likely
to invade drier desert habitats in the Sonoran Desert Region in patches dense
24
enough to burn and convert desertscrub to savanna-like grassland. In Hawaii and
some areas on the Mexican Plateau north of Mexico City, recurrent fires in dense
Natalgrass stands threaten natural vegetation and native species. It is listed as an
alien pest species in Hawaii.
South of Nogales, Sonora, dense
Natalgrass stands along the highway
right-of-way burns regularly. In one area,
a fire spread up a grassland slope and
burned hop bush (Dodonaea viscosa) and
other shrubs to the ground. It has
colonized the canyon bottom and is
invading the adjacent south-facing slopes
of Pima Canyon in the Santa Catalina
Mountains near Tucson. In the Mule
Mountains five miles west of Bisbee in
southeastern Arizona, it grows densely
with velvet mesquite (Prosopis velutina)
Natalgrass fire in highway median, south
and ocotillo (Fouquieria splendens) in
of Nogales, Sonora. Photo: T.R. Van
desert grassland on a south-facing slope Devender
very similar to those south of Nogales. It
is intolerant of cold and dies back to the base at the first frost. Cold temperatures
probably prevent it from expanding into many higher or more northern areas in
Arizona. However, its behavior in warmer areas to the south suggests that it is
prudent to watch it in the southern Arizona borderlands where many tropical plants
and animals reach their northern distributional limits.
Distribution
Natalgrass is native to South Africa but is now introduced in the warmer parts of the
world, including tropical Latin America in North and South America. In the United
States it is mostly found in Florida, west along the coast of the Gulf of Mexico to
south Texas, southern Arizona, and Hawaii. It also occurs in Maryland, Virginia, New
Mexico, southern California, Puerto Rico, and the Virgin Islands. In Sonora, zacate
rosado is common in the Nogales-Imuris area (north-central) and from Tepoca to the
Yécora-Maycoba area (eastern). It is locally present in Sonoran Desert in central and
west-central Sonora, and southward and eastward into more tropical areas.
In Arizona Natalgrass is locally common in Pima County in the Santa Catalina and
Tucson Mountains, and Tucson, and in Cochise County in the Mule Mountains west of
Bisbee. It is uncommon in Santa Cruz County in the Santa Rita Mountains.
Habitat
Natalgrass is most common in Arizona on disturbed roadsides along paved highways
in desert grassland 3000 to 4000 feet. In eastern and northern Sonora, and in the
Mule Mountains west of Bisbee, it has spread into natural desert grassland. It is less
common in the Arizona Upland Sonoran Desert down to 2400 feet and oak woodland
up to 5700 feet.
In Sonora, it is common in desert grassland northeast of Imuris and south of Nogales
(to 4300 feet), and near Maycoba in the Sierra Madre Occidental in eastern Sonora
(to 5400 feet). It occurs in desertscrub, foothills thornscrub, and tropical deciduous
forest from near sea level in the Guaymas area through the transition into oak
woodland (3600 feet) above Tepoca in eastern Sonora.
25
History
This attractive grass with its long purplish-pink, silky hairs on the fruit and open
inflorescences has been grown as an ornamental. It was grown for forage in the
southeastern United States. In the Arizona Flora published in 1951, Natalgrass was
only reported in Pima County in the Santa Catalina Mountains near Tucson. Since
that time it has spread into many areas in the Tucson area and appears to be
expanding its range in the Arizona-Sonora borderlands.
What can be Done?
Management and control methods are not well known. It should not be planted as an
ornamental and should be pulled by hand in areas of conservation concern.
Other Common Names: rose Natalgrass, Natal redtop, zacate rosado, espiga
colorada, pink feathergrass, rubygrass, Holme's grass, blanketgrass.
Links
Utah State University Intermountain Herbarium Grass Manual (distribution map in
the United States)
USDA Natural Resources Conservation Service Plants Profile
Fact sheet on Natalgrass in the Pacific Islands
References
Gould, F. W. 1977. Grasses of the Southwestern United States. University of Arizona
Press, Tucson.
26
SAHARA MUSTARD (BRASSICA TOURNEFORTII)
What is it?
Numerous Old World mustards have invaded North America. Of these Sahara
mustard (aka several other names) is the newest and by far the worst. It is a robust,
fast-growing, drought-tolerant winter annual that prefers sandy soils. The basal
rosette of divided hairy leaves can span three feet in wet years. The nearly leafless
flowering stems branch profusely and grow to a height of about two feet, creating
the appearance of a shrub from a distance. The small light yellow flowers are selfpollinating, so each of the thousands of them sets a seed pod. Large plants produce
up to 9000 seeds. Dried plants break off at the base and tumble like Russian thistle
(tumbleweed, Salsola tragus), spreading seeds rapidly across the landscape. When
wet, the seeds are sticky with mucilage and can be transported long distances by
animals and perhaps vehicles.
All photos: Mark Dimmitt
Several other exotic mustards are also invasive threats to the Sonoran Desert. Most
of them have been here a long time and have already invaded most suitable habitat;
we can hope they will not cause further damage to communities. Black mustard
(Brassica nigra and similar spp.) can also grow to nearly three feet tall. It is
distinguished from Sahara mustard by its smaller leaves and larger, bright yellow
flowers. London rocket (Sisymbrium irio) is a major pest in gardens as well as
roadsides and undisturbed desert areas. It has bright shiny leaves and flower stalks
up to 2 feet tall with small bright yellow flowers.
27
Arugula (aka rocket salad, Eruca vesicaria
sativa) is a culinary herb with one-inch
whitish to yellowish fragrant flowers. The
plants can grow to 5 feet tall in wet years
as in the image at right. It is now the
dominant plant in much of the area along
Interstate 8 from Gila Bend west to the
Maricopa County line, a distance of 45
miles. Along this stretch it extends on
both sides of the freeway as far as the
eye can see. It has been there for many
decades and is apparently spreading
slowly. Because of the stealthy spread
and its remote location, its invasion has
gone largely unnoticed except by
botanists. Though a significant local
threat, arugula is a minor problem
compared to Sahara mustard.
Almost everything visible in this scene is
arugula. The plants are nearly as tall as
the widely-scattered creosotebushes
barely visible in this scene taken in March
2005.
Why is it a Threat?
This dune evening primrose seedling
(Oenothera deltoidea, right) will soon be
overgrown by the Sahara mustard
seedlings next to it.
Sand verbena (Abronia villosa) struggling
to survive beneath a large Sahara
mustard that germinated at the same
time.
This weed grows very fast, smothering native herbaceous plants and even competing
with shrubs for light and soil moisture. The famous wildflower fields of the sandy
valleys of Lower Colorado River Valley Sonoran Desertscrub are in danger. In the
winter-spring of 2005 about three-quarters of the prime display areas were overrun
with Sahara mustard in California and Arizona. Fortunately it does not do well in
every year. It is known that a freeze can kill the plants and give native flowers a
chance to grow and reproduce. However, freezes are uncommon in the low desert.
28
Now: 2005
Then: 1998
What we have lost: These two scenes were both photographed in the northern end
of the Mohawk Dunes in western Arizona. In 2005 Sahara mustard covered 70-90%
of the surface area at this location. Almost no native wildflowers bloomed here in
2005.
In wet years Sahara mustard covers the ground almost 100% and can carry fire
when it dries. It is a frightful thought that hyperarid desert, including sand dunes,
can burn because of this weed. There have already been documented fires in the
dunes west of Blythe, CA and the Pinta sands in the Cabeza Prieta Wildlife Refuge.
This latter site is a remote, uninhabited, and previously pristine habitat. Most
Sonoran Desert plants cannot tolerate fire; burned areas become wastelands of
nearly pure Sahara mustard.
Snow Creek Canyon on the south side of
the San Jacinto Mountains near Palm
Springs, CA used to be covered in huge
carpets of pink, yellow, and white flowers
in wet springs. Now it is almost 100%
Sahara mustard.
This area of sand dunes in the Chuckwalla
Valley, CA (west of Blythe) burned, killing
most of the creosotebushes. Sahara
mustard was the fuel.
This is the worst invasive plant in the Sonoran Desert in terms of area covered
and damage inflicted on the biotic community. In riparian communities saltcedar is
its rival.
Distribution
29
Sahara mustard is abundant in the Desert Southwest at low and mid elevations from
southeastern California to southern Nevada and south into Baja California and
Sonora. It's rare in southern New Mexico and western Texas. It extends to the edge
of the tropics in Mexico.
It is native to many areas of the Old World from north Africa and the Middle East
east to southern Europe and Pakistan.
Habitat
It is most abundant in Lower Colorado River Valley Sonoran Desertscrub and lower
Mohave Desertscrub. It's currently uncommon in Arizona Upland Sonoran
Desertscrub, and rare in chaparral and desert grassland. It favors sandy, disturbed
soils at low elevations, but its range is expanding rapidly into undisturbed soils
including rocky hillsides in Arizona Upland. The literature lists its elevational range as
250 to 2800 feet, but it has recently been found above 4100 feet.
One way that weeds invade new habitats:
This huge field of dried Sahara mustard
This mound of imported soil in Tucson, AZ
near very arid Parker, AZ was several
was infested with seeds of Sahara
miles long. If it catches fire, the houses in mustard and London rocket.
the background are at risk as well as the
few native plants left.
History
This recent invader probably arrived in North America as a contaminant in crop seed.
The first record is from California's Coachella Valley in 1927. It was first discovered
in Arizona-Sonora in 1957 on Mexico Highway 2 near Yuma. By the 1970s it was
widespread in the low desert in Arizona, California, Baja California, and Sonora. It
doesn't seem to have caused much alarm until the early 1990s when people began
to realize how much habitat it was overrunning.
Sahara mustard was first collected in Tucson in 1978, and in 1991 was reported as
rare. Today it is widespread and locally common in the metropolitan area and
surrounding suburbs.
What can be Done?
In small areas Sahara mustard can be eradicated by pulling plants before they
mature seed. This is most effective in new invasions where a seed bank has not been
established.
30
Control in the thousands of square miles of remote desert habitat seems almost
hopeless. It is unlikely that a biological agent, if found, would be approved because
many important crop plants are in the genus Brassica (e.g., cabbage, cauliflower,
broccoli, brussels sprouts). There are also numerous native mustards that might be
threatened by a biological agent.
In selected areas herbicide treatment may be effective. Sahara mustard tends to be
the first annual to germinate after a rain, so early treatment may reduce its
abundance and allow later-germinating natives to establish.
The spread of Sahara mustard can be reduced by controlling it along roads, which
provide corridors for rapid invasion into new habitats.
Other Common Names: Asian mustard, Moroccan mustard, desert mustard,
southwestern mustard, Mediterranean mustard, Mediterranean turnip, wild turnip,
prickly turnip, turnip weed.
References
Felger, R.S. 1990. Non-native plants of Organ Pipe Cactus National Monument. Tech.
Rep. 31. Tucson: Cooperative National Park Research Studies Unit.
Felger, R.S. 2000. Flora of the Gran Desierto and Rio Colorado of Northwestern
Mexico. Tucson: University of Arizona Press.
Minnich, R.A. and A.C. Sanders. 2000. Brassica tournefortii Gouan. In: Bossard, C.C.,
J.M. Randall, and M.C. Hoshovsky. eds. Invasive Plants of California's Wildlands.
University of California Press, Berkeley and Los Angeles. 360 pp.
Tellman, Barbara (ed.). 2002. Invasive Exotic Species in the Sonoran Desert Region.
University of Arizona Press.
Van Devender, T.R., R.S. Felger, and A. Burquez M. 1997. Exotic Plants in the
Sonoran Desert region. 1997 Symposium Proceedings, California Exotic Pest Plant
Council. Website
31
TAMARISK, SALTCEDAR, ATHEL TREE (TAMARIX SPP.)
What is it?
Tamarisk is a general term for several species of Old World shrubs and trees in the
genus Tamarix with scalelike leaves on very thin terminal twigs.
Saltcedars are large shrubs or small trees 8-16 feet tall and usually less wide. They
have tiny, triangular, scale-like leaves that are winter-deciduous. The flowers are
pink to near-white, densely crowded along branched terminal spikes; they appear
from January to October. Fruit and seeds are tiny, brown, inconspicuous. The several
species introduced to North America have been labeled Tamarix chinensis (our
current choice for southern Arizona plants), T. ramosissima, T. pentandra, T.
parviflora, and T. gallica. They are very similar in appearance and are hybridizing, so
distinguishing among them is difficult. Apparently the hybrid populations are the
most invasive.
Young saltcedar (Tamarix cf. chinensis) in
flower. Photo: Steve Dewey, Utah State
University; www.forestryimages.org
Tamarix chinensis branch with flowers. The
tiny triangular leaves stick out from the stems,
giving the twigs a prickly feel. Photo: T.R. Van
Devender
Athel tree (Tamarix aphylla, also called saltcedar) is a large evergreen tree to 50 feet
tall and wide with virtually no leaves (reduced to tiny scales) and inconspicuous
whitish flowers. It was long thought to be sterile and therefore at most mildly
invasive, but it is reproducing from seed in some localities. It has been doing so at
Lake Mead for 30 years, and is hybridizing with the deciduous saltcedars.
32
A young-mature athel tree at Lake Mead.
Photo: Elizabeth Powell
Closeup of athel tree twigs showing the tiny
scalelike leaves and small white flowers.
Photo: Mark Dimmitt; inset: Elizabeth Powell
Australian pines (Casuarina spp.) could be confused with tamarisks. They have
similar thin branches and scale-like leaves. Casuarinas don't seem to be invasive in
the southwestern U.S., where they are found mostly in landscaped areas.
Why is it a Threat?
Tamarisks are extremely invasive in riparian communities, often nearly completely
replacing native vegetation with impenetrable thickets. They are extremely
competitive against native vegetation because they are aggressive usurpers of
water. They also sequester salt in their foliage, and where flooding does not flush out
soil salts the leaf litter increases the salinity of soil surfaces. Dense stands of
saltcedars support lower biodiversity than the natural communities they displace.
This stretch of Tonto Creek above
Roosevelt Lake in Arizona is choked with
Tamarix chinensis. Most of the green on
the valley floor is this saltdecar. Photo:
Mark Dimmitt
Several miles of Greene Wash south of
Casa Grande, AZ is dominated by athel
trees. These may have propagated by
pieces of branches that wash downstream
in floods and take root, or they may be
seeding. Natural washes in this region are
vegetated by desert ironwood trees
(Olneya tesota) and blue palo verde
(Parkinsonia florida). Photo: Mark
33
Dimmitt
Distribution
Tamarisks are almost throughout the Southwest below about 6000 feet elevation. In
Arizona they are widespread, especially south of the Mogollon Rim and in the Grand
Canyon.
Habitat
Tamarisks occur mostly on low ground where water collects. They are most abundant
in riparian habitats, both natural and artificial, often in extensive pure stands. They
are less common in drier places. They thrive in alkaline and saline soils.
History
Various species of tamarisks were in cultivation in the United States in the early
1800s. The National Arboretum released T. pentandra in 1870. Tamarisk was first
noticed to be escaping from cultivation in 1880, and by the end of the century it was
common along southern Arizona and Texas rivers.
What can be Done?
There are teams of "tammywackers" in several states that are making progress in
local areas. Specially modified jacks are used to grip and pull trees up by their roots.
Cutting and treating the stumps with herbicides gives good control. Aerial spraying is
being used in large areas where tamarisks have completely taken over. In areas too
large or too remote for manual control, flood management can reduce the
dominance of saltcedars. Periodic floods prevent saltcedars from forming dense
thickets, permitting native trees and substory plants to establish and maintain
codominance.
References
Gaskin, J.F. and P.B. Shafroth. 2005. Hybridization of Tamarix ramosissima and T.
chinensis (saltcedars) with T. aphylla (athel) (Tamaricaceae) in the southwestern
USA determined from DNA sequence data. Madroño 52(1):1-10.
34
ONIONWEED (ASPHODELUS FISTULOSUS )
What is it?
Onionweed is an herbaceous perennial in the lily
family (Liliaceae) to about a foot tall and almost as
wide. Clusters of long, tapering, round, hollow
leaves very much resemble chives or scallions.
Leaves sprout after winter rains. Flowers appear in
spring. Plants die to the ground during dry season.
The flat flowers are less than a half-inch across and
have six petaloid parts, each white with pink center
line. They are sparsely distributed on branched
spikes to almost two feet tall.
Fruits are 1/8-inch round capsules.
Mature plant in flower. Photo:
Mark Dimmitt
Onionweed might be confused with some native
onions (Allium spp.) Allium macropetalum (desert
onion) is a much shorter plant with leaves rarely
more than four inches tall. Taller native onions grow
in different habitats than onionweed.
Closeup of flower. Photo: Mark Dimmitt
Dried plant with seed capsules. Photo:
USDA
Why is it a Threat?
Onionweed is an aggressive invasive species. Introduced as an ornamental, it easily
escapes cultivation into surrounding unirrigated land. It seeds prolifically and can
establish large populations quickly. It is unpalatable to cattle and apparently to most
wildlife, so it is very persistent once established. To date it tends to invade
disturbed ground, so it is unclear whether it will be a threat to natural communities.
35
Distribution
Native to southern Europe, Mediterranean Africa, and Western Asia. In the United
States onionweed occurs in California (in several coastal southern counties), Arizona,
New Mexico, and Texas. Also known to be in Mexico. It is a noxious weed causing
problems in Australia. Arizona infestations are primarily in the southeastern corner of
the state. A few small infestations have been found in Tucson. Reported but
unverified in Ajo.
Habitat
In the Sonoran Desert region this weed
seems to do best in areas above the
desert that receive moderate winter
rainfall. A well-established population in
suburban Tucson was reduced to only two
plants after the severe drought of 2002.
Plants have been found in Arizona from
about 2000 feet elevation to at least 4500
feet.
History
Onionweed invading a roadside in
Plants introduced into the United States in southeastern Arizona. Photo: USDA
the 1980s may be the founders of our
invasion. They were offered for sale in Alpine, Texas and Phoenix, Arizona as early as
1984. Some of the original US plants were collected from a naturalized population
near Saltillo, Coahuila, Mexico, where the species was documented in 1930.
What can be Done?
Some nurseries offer onionweed as an
ornamental even though it is a prohibited
noxious weed in many states as well as a
federally listed noxious weed. Do not buy
it or plant it, and eradicate it if it is
established on your property.
Pulling the plant is usually not effective.
The top breaks off leaving the tuberous
roots underground. They must be dug up
by the roots or sprayed with herbicide.
A flowering plant in desert grassland with mesquite. Other common names: pink asphodel,
hollow-stemmed asphodel
Photo: USDA APHIS Archives,
www.forestryimages.org
36
Links
USDA Plant Database Profile
InvasiveSpecies.org onionweed page
The Nature Conservancy's Invasive Species Initiative
References
(The literature on this species is very sparse
37
.)
RED IMPORTED FIRE ANT (SOLENOPSIS INVICTA)
What is it?
The red imported fire ant (RIFA) is a small reddish brown ant from South America .
There are six known species of fire ants (Solenopsis spp.) in the United States, three
of which are found in Arizona. These three species are the southern fire ant (S.
xyloni), and two species of desert fire ant (S. aurea and S. amblychila). RIFA has not
established in Arizona, but is present in the bordering states of New Mexico and
California. It was discovered near Yuma, Arizona but was exterminated.
Adult red imported fire ants. Photo: USDA RIFA workers marked with wire bands.
APHIS PPQ Archives,
Photo: Bart Drees
www.forestryimages.org .
RIFA are small but highly aggressive. They inject a necrotising, alkaloid venom when
they sting. The stings result in painful, itchy, and persistent pustules, and sometimes
in severe allergic reactions. Five million people are stung each year in the
southeastern United States. About 25,000 of these people require medical
consultation. When a fire ant mound is disturbed, workers boil to the surface, run up
any legs, arms, etc. in the vicinity, grab the victim's skin in their mandibles and sting
synchronously in response to the slightest movement. The attacks are coordinated
and dozens or even hundreds of workers sting in unison.
Fire ants swarming boot after mound
disturbance. Photo: Bart Drees.
Pustules from RIFA stings. Photo: Murray
S. Blum, The University of Georgia,
www.forestryimages.org
Fire ants live in colonies that may have 100,000 to 500,000 ants. The queen of the
colony can lay from 1500 to 5000 eggs per day, never leaves the nest and can live
38
for many years. Worker ants take care of the queen and her eggs, build the nest,
defend the colony, and find food. Preferred food of fire ants consists of protein-rich
sources such as insects and seeds. Winged male and female ants fly from the colony
in the spring and summer to mate in the air. The males die and the females become
queens that start new colonies.
Only the red imported fire ant has a median clypeal tooth and a striated
mesepimeron; these may be difficult to see at first. RIFA also have an antennal
scape that nearly reaches the vertex, a post-petiole that is constricted at the back
half, and the petiolar process is small or absent. Of the native fire ant species, the
southern fire ant (Solenopsis xyloni) looks the most like the red imported fire ant. It
can be identified by its brown to black color, well-developed petiolar process, and no
median clypeal tooth. Desert fire ants (Solenopsis aurea and S. amblychila) are both
yellowish-red to reddish-yellow and have a well-developed petiolar process. RIFA can
also be identified by the proportion of large to small workers in disturbed mounds. If
half the workers in disturbed mounds are large and dark, it is RIFA. If only a few
large ants appear relative to hundreds of small ants, it is non-RIFA.
Side view of adult RIFA worker. Photo:
USDA APHIS PPQ Archives,
Median clypeal tooth can be seen here on
www.forestryimages.org.
head above the mandibles. Mandible has
4 teeth. Photo: Carl Olsen
39
Table: Characteristics of RIFA and RIFA mounds
Characteristic
Description
RIFA
# of node segments
2
# of sizes of workers
Many (polymorphic)
Size of workers
3 – 7 mm
Shape of thorax
Uneven
# of antennal segments
10 with two-segment club at tip
# pairs of spines in thorax
None
Color
Reddish brown, abdomen darker
Stinger
Present, inflicts pain, leaves white pustule (pustule is not an
allergic reaction)
Mound
Material
Formed from excavated soil
Size
Wider than a dinner plate at its base
Shape
Amorphous, often oval shaped like a mountain cone
Visibility
Above ground, 4” to 24” tall
Entrance
None visible, ants access mound through subterranean tunnels
that spoke out from the central mound
Texture
Has a fresh-tilled appearance, especially after a rain
Size variation in RIFA worker ants and
queen on the right. Photo: S. Porter.
RIFA mounds have a fresh tilled
appearance. Photo: Bart Drees.
Why is it a Threat?
RIFA colonies are extremely destructive. They dominate their home ranges due to
their large numbers and aggressiveness. The lack of natural enemies results in
population booms in areas they invade.
RIFA alter the composition of the ecological communities in the areas they invade.
They outcompete and frequently eliminate native fire ants. They also compete with
other animals for food and alter abundance of prey species. RIFA attack eggs and
40
young of many bird and reptile species. In areas of high infestation, RIFA have
significantly reduced northern bobwhite quail populations (Allen et al. 1995) and may
completely eliminate ground-nesting species from a given area (Vinson and Sorenson
1986). They also attack small mammals such as rodents and have been known to
attack and sometimes kill newborn deer and cattle. Due to a 10-20 year lapse before
bird population reductions are observed, it is suggested that actual effects of RIFA on
animal populations may be underestimated (Mount 1981). Natural plant ecosystems
could potentially be impacted as well. RIFA predates upon solitary bees that are
pollinators of certain plants (Vinson 1997) and move and feed on large quantities of
seeds.
Tricolor heron chick being attacked by fire RIFA feeding on plant nectar. Photo: S. B.
ant workers. Photo: Bart Drees.
Vinson.
Stings from RIFA create health problems for many humans. Fire ants sting
repeatedly and venom is injected from the poison sac with each sting. RIFA venom
has a high concentration of toxins that cause an intense burning and itching that
lasts for an hour and is followed by a blister that becomes a white pustule. Broken or
scratched pustules can result in secondary bacterial infections and permanent scars.
In some individuals, severe allergic reactions can occur resulting in anaphylactic
shock and even death (Dowell et al. 1997).
RIFA worker biting and stinging human.
Photo: Texas Department of agriculture
file photo.
Secondary infection following RIFA sting
on hand. Photo: Texas Department of
Agriculture file photo.
RIFA cost the US billions of dollars a year in damage to agricultural crops and
equipment, livestock, wildlife, public health, and electrical equipment such as air
41
conditioners, traffic signal boxes, electrical and utility units, telephone junctions,
airport landing lights, electric pumps for oil and water wells, computers, and even
car electrical systems. Control methods for RIFA are extremely costly.
Fire ant mound in electrical utility
housing. Photo: S. B. Vinson.
RIFA in traffic control relay switch box.
Photo: Bart Drees.
Distribution
RIFA are native to South America and were brought to the US sometime around the
1930's. They now occupy more than 275 million acres of land in the US and are
found in Florida, Georgia, Alabama, Mississippi, Arkansas, South Carolina, North
Carolina, Texas, Louisiana, Tennessee, New Mexico , Oklahoma, and California. They
invade via transported nursery stock, honeybee colonies, and on empty trailers and
trucks. Cold temperatures may limit the northward spread of RIFA in the US and the
westward spread may be limited by drier conditions. Natural dispersal occurs on
flowing water. Areas with seasonal flooding are vulnerable to RIFA invasion.
RIFA colony floating in flood water. Photo: RIFA colony emerging from flood water.
Bart Drees.
Photo: Bart Drees.
Habitat
In infested areas, colonies are common in lawns, gardens, school yards, parks,
roadsides, and golf courses. Nests generally occur in sunny, open areas and are most
common in disturbed and irrigated soil. RIFA mounds are 4 to 24 inches tall and
have no visible surface entrance. Mounds are accessed through subterranean tunnels
that spoke out from the central mound. Non-RIFA mounds rarely exceed an inch or 2
in height. RIFA mounds have a fresh-tilled appearance, especially after a rain.
42
Typical RIFA mound. Photo: USDA APHIS
PPQ Archives, www.forestryimages.org .
Profile diagram of RIFA mound. Photo:
Texas Cooperative Extension file photo.
History
RIFA are believed to have arrived in the southern United States around the 1930's on
ships from South America as ballast waters were dumped or goods were unloaded.
Their range expanded rapidly and today they occupy 13 US states and Puerto Rico .
What can be Done?
RIFA is a regulated species in Arizona. To keep RIFA out of Arizona, the Arizona
Department of Agriculture has been conducting surveys at high-risk sites such as
nurseries, parks, truck stops, etc. In 2004, all samples collected were negative for
RIFA. The drier climate in Arizona is a limitation for this species, however, as we
irrigate more lawns, agricultural fields, and golf courses, we increase our chances of
a successful RIFA invasion. Once RIFA has established in an area, the chances of
eradicating it are slim and control becomes the primary means of fighting its spread.
It is vital that we prevent the spread of this species. RIFA very easily travel in potted
plants and soil and in our vehicles. If RIFA is detected, citizens should contact the
Arizona Department of Agriculture for confirmation and eradication. Eradication
methods are complex due to the life cycle of the species and should be conducted by
trained individuals.
Links
Arizona Department of Agriculture Red Imported Fire Ant Update
Invasivespecies.gov – a gateway to Federal efforts concerning invasive species
Texas Imported Fire Ant Research and Management Project
University of Florida Red Imported Fire Ant Site
US Department of Agriculture APHIS Imported Fire Ant Information
43
References
Allen, CR, Lutz RS, and Demarais S. 1995. Red imported fire ant impacts on northern
bobwhite populations. Ecological Applications 5(3):632-638.
Dowell, RV, Gilbert, A, and Sorenson J. 1997. Red imported fire ant found in
California . California Plant Pest and Disease Report 16(3-4) June-September: 50-55.
Mount RH. 1981. The red imported fire ant, Solenopsis invicta (Hymenoptera:
Formicidae) as a possible serious predator on some southeastern vertebrates: direct
observations and subjective impressions. Journal fo the Alabama Academy of Science
52:71-78.
Vinson SB. 1997. Invasion of the Red Imported Fire Ant (Hymenoptera: Formicidae)
Spread, Biology, and Impact. American Entomologist 43(1):23-29.
Vinson SB, Sorenson, AA. 1986. Imported Fire Ants: Life History and Impact. The
Texas Department of Agriculture. P.O. Box 12847 , Austin , Texas 78711 .
44
ARGENTINE CACTUS MOTH (CACTOBLASTIS CACTORUM)
The adult cactus moth is not distinctive; there
are thousands of species of small brown moths.
The egg sticks and larvae, however, are easy to
recognize. Photo: Susan Ellis, USDA APHIS PPQ
www.forestryimages.org
Prickly pear pad hollowed out by larvae of the
Argentine cactus moth. Photo: Les Tanner,
Northwest Weeds, www.forestryimages.org
What is it?
The Argentine Cactus Moth (aka Cactoblastis cactus moth) is a small (22-35 mm)
grayish-brown moth. The larvae are 25-30 mm in length and bright orangish-red
with large dark spots that form cross bands. In Florida there can be three
generations in a year. The eggs are laid in a series of up to 140 that creates a chain,
looking like a stick or spine on the surface of the prickly pear pad (cladode). Upon
hatching the larvae burrow into the pad and begin feeding gregariously on the
tissues. This feeding consumes the cladode completely and the larvae move to other
ones before pupation.
The distinctive "egg stick". Photo: Susan Ellis,
USDA APHIS PPQ www.forestryimages.org
Larvae inside a prickly pear pad. Photo: Susan
Ellis, USDA APHIS PPQ www.forestryimages.org
Why is it a Threat?
As a natural feeder on prickly pears (Opuntia species) the caterpillars of this moth
are capable of destroying plants and populations of these plants. Prickly pear cacti
are popular in residential and commercial landscapes throughout the southwest US
and Mexico . Additionally there is widespread and valuable commercial and
traditional use of the plants in Mexico. Opuntia production of food for humans and
livestock are the major uses. It is estimated between 2% of the value and production
from agriculture in Mexico is from Opuntia.
45
Top left: A field of prickly pears (Opuntia ficus-indica) being grown for nopales (edible pads) or tunas (edible fruits)
near Hermosillo, Sonora. Top right and bottom left: Tunas for sale in Hermosillo market. Bottom right: Tunas
prepared to eat. Photos: T.R. Van Devender
Widespread invasion by this moth could lead to extensive destruction of natural
Opuntia populations that serve as food for wildlife such as deer, javelina, rodents,
and coyotes. Birds use prickly pears as nesting sites.
Distribution
The moth is native in the South American countries of Argentina , Brazil , Paraguay
and Uruguay.
It was introduced into Australia in 1926 as a control for the invasive spread of prickly
pears that had been introduced as animal fodder. Introduction has occurred in
African, Asian and island countries since then.
The arrival in Florida may have natural dispersion from the West Indies or on
imported plants.
Habitat
46
Suitable habitat in the U.S. has not been
determined. It can live on many species
of prickly pears, but it is not known
whether it can tolerate the arid climate of
the Southwest.
If Cactoblastis can invade the Sonoran Desert,
prickly pears will virtually disappear from the
landscape. Photo: Mark Dimmitt
History
The moth is native to several South American countries. It was discovered in the
Florida Keys in 1989 and has now spread north to South Carolina and east into
Alabama
What can be Done?
Monitoring Opuntia in nurseries and home landscapes in the path of expansion of the
range of Cactoblastis for evidence of infestation will be critical for early detection.
Research into control methods is being conducted, looking at chemical, biological and
sterile insect techniques (SIT).
Control by available insecticides may be appropriate in nursery and small landscape
settings, but not in widespread landscapes or agriculture.
Specific Biological Control agents (predators) have not been identified and study in
the home range of the moth is continuing.
Sterile Insect Techniques is a process of releasing sterile males into a population,
they breed with fertile females resulting in sterile eggs, thus fewer offspring.
Studies with this technique will take place in 2005.
47
The oozing wounds on this prickly pear pad are
symptomatic of several species of cactus borers,
not necessarily Cactoblastis. Photo: USDA
This saguaro seedling is infested by the native
blue cactus borer (Cactobrosis fernaldialis). The
larva of this moth is bluish in color and do not
feed in colonial groups. This native rarely causes
lethal damage to larger cacti. Photo: Mark
Dimmitt
Links
National Invasive Species Council " invasive species of the month" for March 2005
University of Florida Featured Creatures: the cactus moth
European and Mediterranean Plant Protection Organization (EPPO)
References
Solis, M. Alma, Stephen D. Wright and Doria R. Gordon. 2004.
Tracking the Cactus Moth Cactoblastis cactorum Berg.as it flies and eats its way
westward in the US .
News of the Lepidopterists' Society, Vol. 46 Number 1.
Soberon, J., J. Golubov, and J. Sarukhan , 2001.
The Importance of Opuntia in Mexico and Routes of Invasion and impact of
Cactoblastis cactorum (Lepidoptera: Pyralidae).
Florida Entomologist 84 (4).
48
4
Data Collection
49
DATA COLLECTION PROCESS
GROUP PROJECT
Initially during training the project will be carried out in groups with ASDM staff
supervising data collection. After these group outings, volunteers can choose to be part
of a small group that works together to monitor specific sites.
For organized, small group outings, one volunteer will check out the resource kit from
ASDM which will include a GPS unit, a digital camera, a handheld pc and other
resources to aid with identification and data collection. Only one GPS, camera, and
handheld pc is needed per group outing. One person from the small group will be in
charge of uploading data files into the web-based data form after returning from the
field. The data record will include the names of all participants in the small group.
INDIVIDUAL PROJECT
Volunteers may choose after initial training to work individually either at assigned sites
or on personal hiking/camping/birding outings. Volunteers choosing this method should
still have a companion with them in the field for safety reasons.
MONITORING SITES
The INVADERS Team at ASDM is putting together a network of local partners involved
in invasive species prevention, monitoring, control, and eradication. Monitoring sites will
be chosen based on recommendations and requests from these local partners. In some
cases, this may be an agency or organization requesting help with surveys in previously
unmonitored areas. For cactus moths, volunteers will monitor nurseries, gardens, and
other areas as requested by the Arizona Department of Agriculture. Other sites may
include areas that underwent eradication previously and the purpose of monitoring will
be to determine eradication success. It is our goal to target areas that are most in need
of monitoring.
We also encourage volunteers to collect data when out in the field on recreational
outings. It is important that you be aware of the rules regarding public vs. private
property and various agency requirements for data and specimen collection. These are
outlined later on in this section of the handbook.
50
SAFETY IN THE FIELD
Due to the field-oriented nature of the INVADERS Program, your work will present you with the
inherent physical risks posed by walking in a natural environment and getting to field sites in
Museum and/or personal vehicles. We recommend you follow these suggested safety
precautions:

Do not walk where you cannot see your feet. Thick vegetation may hide venomous animals
or uneven terrain from view.

If searching for species patches from a vehicle, always go in teams. Vehicle drivers should
pay attention to the road, and passengers can look for target species.

When surveying on roadsides, pull vehicles far off the road, taking care to park on a firm
surface. Be aware of passing traffic and stay clear of traffic lanes while collecting data.

Do not hike alone.

Carry a topographic map or trails map of areas in which you are hiking.

Inform someone not in your party of where you are going and when you plan to return.

Bring a cell phone (but be aware that many remote areas in our region are out of service
range).

Bring sufficient water and sun protection.

If you have known allergies or other medical conditions that might require that you take
medications in the field, bring your medications with you.
We will not ask you to perform a service that is beyond your comfort level, so please be direct if
you are ever concerned about field conditions and the nature of our work on any outing.
51
INVADERS PLANT DATA COLLECTION
Preparation for site visit

Prior to visiting your field site for data collection make sure you have good maps
and directions for getting to your site. Do not forget to fill up your vehicle’s gas
tank and bring extra water, particularly if you are traveling far from inhabited
areas. If you plan on working far from trails and roads, you should also have
topographic maps of your area with you. Make sure that you have permission
to be in that area. If you are not sure if collecting data in a particular area is
permissible, you can contact a member of the ASDM Invaders Team to verify or
check into the status of that particular site.

Make sure that you let someone know where you will be going and when you
expect to return. This is important to do even when you are with a group of
people. You should always have a companion when working in the field.

Check the weather before you head to the field site. You should not work in
adverse weather conditions such as thunder and lightning storms. Be aware of
the danger of flash floods particularly if you are working in riparian areas,
washes, or flood prone areas. While it may be sunny and clear where you are
working, precipitation in higher elevations can produce flash floods that are
swiftly carried down washes to areas away from the center of the storm.

Make sure you bring plenty of water, sunscreen, a hat, appropriate clothing
and footwear, and a first aid kit. Many of you will be walking off trails and
roads into desert areas so shorts and sandals are not recommended. If you
have a cell phone, bring that with you. Keep in mind that you may be in remote
areas where you are out of service range. This is why it is so important to let
someone know where you are going and when you will be back. If you have
known allergies or other medical conditions that might require that you take
medications in the field, make sure you put those medications in your field pack.

Check your field equipment before you leave. Turn on your GPS units and
cameras to make sure they are working properly and have good batteries in
them. Bring extra batteries with you just in case. Make sure your pencils are
sharpened and that you have sufficient blank data sheets for the number of areas
you plan on visiting. Check that you have a sticky note pad, your field notebook,
a working sharpie pen, a thermometer, the Invaders ID cards, and your Invaders
handbook. If you feel that the handbook is too bulky for the field, make sure you
bring the most important components with you: data protocols, datasheet
definitions, GPS and camera instructions, and the information letter for curious
landowners or others.
52
When you arrive at your field area…

Once you have reached your destination, you will want to make sure that you
bring all needed items with you in a pack, particularly if you are leaving your
vehicle behind. Many unfortunate hikers and researchers carefully bring their
cell phones, enough water, and notebooks only to leave them in the vehicle
and then find themselves in need miles away. Make sure your vehicle is
parked in a safe place – far enough from the road that it does not impede
traffic and do not block roads, driveways, etc. After strapping on your
backpack and locking your vehicle you are ready to enter the exciting world of
scientific data collection.

Be aware of your surroundings. Venomous animals can be found throughout
Arizona. Do not walk where you cannot see your feet. Thick vegetation can
hide venomous animals or uneven terrain from view. Be comfortable with the
area you are working in. If you are leaving roads and trails, make sure you
have good maps, a compass, and feel confident with map navigation.
Where is your search site/route?
The first thing you need to know is where you are going. Will you be looking for
invasive species along a trail or road, following a wash, searching a large area
thoroughly? After you answer this question, you will be able to plan your approach
to the site. If you will be working in the same area as other volunteers and will need
to let them know what sections you have already searched, you should use your
notebook to describe your route and add coordinates if possible. You will be able to
post these notes online for other volunteers to see. If you will be covering whole
parks or trails, you can put that information online as well. Make sure you keep track
of which species you searched for. It will be important for others to know what
species you did not find in a particular area.
You found an invasive species. Now what do you do?
When you reach a site with an invasive, non-native species you should do a visual
survey of your surroundings by walking around the area to assess the extent of the
infestation. After this initial assessment, you will decide whether the invasive species
patch you are defining is a point, or polygon (a linear patch is a polygon).
53
Point: Technically speaking, most patches are polygons unless you have a single plant.
However, when your patch is less than about 5 meters wide, you will call it a point and
take one set of GPS coordinates. The reason for this is that your GPS unit will be
unable to define the outline of a polygon in a patch this small due to the accuracy
limitations of the equipment.
Polygon: When the patch is a polygon of some shape larger than 5 meters wide or a
linear polygon, you will designate the patch a polygon and take multiple sets of GPS
coordinates to define the area.
There will be occasions where you are unable to walk around a patch of an invasive,
non-native species due to steep terrain, dense vegetation, etc. In these cases, you will
need to be innovative in the field providing coordinates as close to the patch as possible
and create expanded notes describing the location, shape, and size of a patch. Your
notes will be important additions to required data fields and should provide land
managers and other interested parties with enough information to assist them with
determining whether a return trip to that site is required for a more detailed survey.
54
If you have questions, concerns, or suggestions related to data collection, we want to
hear from you. Let us know what situations you come across in the field that we can
address in our resource kit to make it more beneficial for volunteers, scientists and
managers, or other institutions that want to implement this program in their local areas.
55
Arizona Sonoran Desert Museum
Pocket PC Units with Integrated GPS units
HGIS Version 8
Fundamentals
Turn unit on and off by pushing the power button once (on the key pad for Trimble units
and on the top front of the Garmin unit).
Always SAVE data before turning the unit off. See instructions on saving data below.
To recharge the unit you will need its power cord and a power source. The cord plugs
into the bottom end of the unit. You can view current main and back-up battery levels by
going to Start – Settings – Systems Tab (at bottom of screen)– Power Icon.
Programs
Your handheld unit is equipped with several programs that may be of use in the field.
For mapping exotic plants you will use HGIS software in conjunction with an internal
Global Positioning System (GPS) unit. These two programs will work together
allowing you to record the exact locations of the exotic plants you find as well as
delineate the exact area and densities of the infestations. During certain projects you
may also make use of Word to take notes about an area or Excel to collect non-spatial
data. All screens can be closed either by hitting the X or OK that will be in the top right
corner.
How to begin mapping
Step 1: Turn on your handheld computer
 Take out your unit and turn it on.
Step 2: Open the HGIS CE8 mapping program
 On the start up screen, tap on START, this will open a drop down list of
programs.
 Choose Programs
 Then choose HGIS CE8 by tapping on the icon
56
 On the first screen chose HGIS_Pro_1 from the drop down
 Choose Start GPS
 Open GPS Port screen will appear. Here you should make sure that:
 Down list = Serial NMEA
 Port = COM2
 Baud = 4800
 Drop
Step 3: Open background maps if available
If you are working on a project with a prepared set of background maps, click on
File and then Open Project (When you first open HGIS, this dropdown is
already showing on the screen). Choose your current project (e.g.
FOBO_EPM, SAGU_TMD_EPM) from this screen. This file is a project file that
will open all base maps (files) needed for orientation during mapping.
NOTE: If there are base files for your project and none of the above files appear,
check that under the Open Project window:
 Folder = All folders or templates
 Type = HGIS Project (HGS)
They should then appear.
 Tap on desired project, HGIS screen with layers open will appear.
57
(Example from Casa Grande).
 In some cases, a project will not be set up for the area you will be working in. In
that case, you can open a general background map by choosing Open Layer
and then clicking on the map file for your area. If there are no map files for the
area you are working in, you can still collect data. You will not be able to see a
background map, but the GPS unit will still tell the handheld computer where the
invasive species patches are. The data you collect will then be mapped on a
topographic map after you upload your files into the ASDM web site.
To clarify, you can still collect data even if you do not have a background map visible
on your handheld screen. As you map invasive species patches, you will see your
points and polygons show up on your white screen.
Now you are ready to begin mapping! Your GPS unit is turned on and the mapping
software is open. It may take a few minutes for your GPS unit to acquire satellites; you
will know when it is ready when an X appears on your screen. A warning screen will
also advise you if there are too few satellites. If you are having trouble getting a fix on
your location, move away from buildings or other structures. Move to higher ground if
you are not getting a fix in a canyon.
How to open and close background maps:
58
Depending on where you are working, different files may now be open on the unit
screen that show boundaries, roads, trails or water features. Additional files may be
open that show grid squares, grid centre points or rectangles that represent sample
locations if those have been set up for your current project. These files can be closed
and re-opened if you would like to customize the background on your screen.
To open layer files with project open
-
Go to File → Layer → Open Layer → Select desired files from list
Only one file can be opened at a time, so you must repeat as
necessary.
To close layer files with project open
-
Go to File → Layer → Close Layer → Select desired files from list
Only one file can be closed at a time, so you must repeat as
necessary.
To open layer files without project open
-
Go to File → Open Layer → Select desired files from list
Only one file can be opened at a time, so you must repeat as
necessary.
To close layer files without project open
-
Go to File → Layer → Close Layer → Select desired files from list
Only one file can be closed at a time, so you must repeat as
necessary.
Step 4: Create new layer files for each day of work.
Two files should be created for each field day; one for any point data you will collect and
one for polygon data. The naming convention for these files is as follows
Your initials, Date (MMDDYY format), park name or area name, point (pt) or polygon
(py)
Example: SS031006CAGRpt or SS031006IRONWOODpy
Special templates have been loaded onto your unit for use when mapping exotic plants.
When you are ready to create your field files described above you will use this template.
If you have a project open:
 Go to File → Layer → New from Template
If you do not have a project open:
 Go to File → New from Template
59
 Select the template named Exotics_2006_ASDM – this file contains all
of the
data fields you will need for the INVADERS program
 Type in file name as described above (e.g. SS031006CAGRpt)
 Select the icon that corresponds to the file type (point or poly)
 Hit OK
 Repeat these steps for second file, either point or poly, whichever has not
yet
been created. You will now go to File → Layer → New from Template
whether
you opened a project initially or not. Then you can select the
Exotics_2006_ASDM template and create your file name and type.
 Hit OK
Step 5: Mapping set-up.
When you encounter the first invasive species to be mapped you need to make sure
you are entering your data into the correct file. This means you have to be in edit mode
in the point or polygon file depending on whether you need to record a single plant or a
large infested area. To see which file you currently have open, go to
 Map → Layer Properties
 This screen will show all layers (files) that you have open
 Click next to edit under the appropriate file you wish to add data to (point or
poly). This will cause a check to appear next to edit for that layer. Only one file
can be edited at a time.
 Close this screen.
 You will need to go back and forth between your point and polygon files as you
collect data in the field.
Step 6: Create Points and Polygons and record data.
Mapping criteria
 Q1). When should you draw a point verses a polygon?
Points should be used for individual plants or patches that are 5m across or less.
The GPS units are only accurate to this level. If you encounter an area less than
5m across with 2 or 3 species present, record one point for each species.
Anything larger should be recorded as a polygon. The template makes it possible
to record up to five species for each polygon described.
 Q2). What should I do if there are more than five species in one polygon area?
If you encounter more than five species in an area you need to create a new
polygon for those extra species. This may mean you have a polygon with only
60
one species in it, or as many as five or more. In this case you may find that the
polygons are different shapes and sizes as the species distribution could be quite
different.
 Q3). What else is there to consider, if possible, when mapping an area?
If possible be aware of natural breaks in the landscape such as similar plant
communities, similar aspect, or slope. Try to delineate roads, pathways, trails, or
disturbed areas from construction, fire or grazing, i.e. map around these things
using one polygon.
But the primary goal is to describe the infested area as precisely as
possible (which will often cross natural breaks or be smaller than the continuous
similar area).
NOTE: It is not possible to record a point at the same time as drawing a polygon.
If you encounter a single plant when traversing a polygon take note of its location
either on paper or mentally and return to it after you have finished the polygon, to
make a point.
NOTE: When drawing polygons it is important to not double back on yourself and
to avoid criss-crossing the lines you have already drawn, as this confuses the
spatial area.
Recording a point. Remember a point is a single plant or a an invasive
species patch
that is smaller than 5m wide.
 Go to Map → Layer Properties
 Check the box next to the appropriate file you wish to add data to
(point)
Now you are ready to record data. To begin, go to the drop down list
located in the top right corner of the screen (tools menu). It is the box that
says OFF before you choose a tool. When you click on OFF, you will see
the drop down list of tools.
o From this tool menu list in upper right corner, choose GPS draw. A
new row of icons will appear at the top of your screen
o To record a point location hit the Star symbol. This will
automatically record your current location and a point will occur on
your screen. Make sure you are standing at the location of the
invasive plant before you mark your point.
o The first point you make will prompt the system to begin Auto
numbering.
o Hit OK.
o Once the point is made, hit OFF in the tools menu.
o Go back to the tool drop down and choose SELECTOne
o Double tap on the point just recorded
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o The template for the point will come up allowing you to enter data
on the species in question. For a single plant (point location) you
need only enter a name under Species1, no cover class is
necessary. Hit the arrow to the right of the Species1 box. Choose a
species. Scroll down to access other fields to be filled out using
drop down lists; slope, aspect, meters to road/water, water type,
disturbance, extent, and surveyor name. (See details below on
filling in data fields)
o NOTE: For fields where you need to type in words you will need to
bring up the keyboard. Do this by tapping the “keyboard” tab at the
top of your screen. Close it by tapping it again
o Close this window using the X in the top right corner.
Continue to make as many points as necessary in this manner.
NOTE: If you try to put a point into a polygon file (or vice versa), a warning
message will appear asking you if you want to continue; say no.
Go back to Map – Layer properties, and make sure you have the correct file in
edit mode.
Recording a polygon. Remember a polygon is an invasive species patch
larger than
5 m wide.
If you are describing an area infested with one or many exotic species
 Go to Map → Layer Properties
 Check the box next to the appropriate file you wish to add data to
(poly)
 Hit OK
 From the right hand drop down tool menu choose GPS draw.
 Choose the green filled polygon shape, labeled Bound.
 The first polygon you make will prompt the system to begin Auto
numbering.
 Hit OK.
 You are now ready to begin walking around the area you wish to
describe.
(When you are actively drawing an area you will see a rectangular bar
rotating
next to the green filled polygon shape).
 Try to return back to where you began your polygon without
overlapping your
lines. When finished Hit OFF. After drawing the polygon, you should
go
back and walk through the entire polygon to as accurately as possible
estimate the plant cover.
 Go back to the drop down tool menu and choose SELECT
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 Double click on the edge of or within the polygon you just created. The
template for the polygon will come up allowing you to enter data on the
invasive species in the polygon.
 You can record up to five species per polygon. For each species, an
associated
cover class is recorded, representing the density of each species in
the area.
(<1%, 1-5%, 5-25%, 26-50% etc).
 Scroll down to access other fields to be filled out using drop down lists;
slope,
aspect, meters to road/water, water type, disturbance, extent, and
surveyor
name. (See details below on filling in data fields)
NOTE: For fields where you need to type in words you will need to
bring
up the keyboard. Do this by tapping the “keyboard” tab at the top
of your
screen. Close it by tapping it again.
 Close this window using the X in the top right corner.
NOTE: If you try to put a point into a polygon file (or vice versa), a warning
message will appear asking you if you want to continue; say no.
Go back to Map – Layer properties, and make sure you have the correct file in
edit mode.
DATA FIELDS IN THE TEMPLATE
1. Auto ID: This field will automatically be filled in. HGIS will number your points
and polygons as you create them.
2. Longitude and Latitude: These fields will also automatically be filled in. The
internal GPS unit automatically records a longitude and latitude for the point you
created. For polygons, you will also see a longitude and latitude in these fields
even though the locational data for your polygon is based on more than one
coordinate.
3. Altitude: This field will already be filled in. The GPS unit automatically records
an elevation in this field.
4. Area Acres: This field will also be filled in automatically. In point records, it will
read 0.000 since a point does not have an area. For polygons, the program
automatically generates a size for your invasive species patch.
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5. Distance_meters: An automatic calculation of perimeter distance shows up in
this field if the feature is a polygon. For a point, it will read 0.000.
6. GPS Date/Time: These fields are also automatically filled in with a date and time
that the internal GPS unit reads from satellites.
7. Species1-5: For each point you create, you should record only one species. If
you have more than one species at the same location, you should create a
separate point for each species. You will notice that in your point file, it gives you
the option of recording more than one species. That is because you use the
same template to create each type of file. You should still only record one
species per point. You may record up to 5 species for each polygon. If there are
more than 5 species, then you should create another polygon in the same
location to record data on the extra species. Use the drop down list to find the
species. All species names are scientific names. Please bring along species
lists to help you identify the correct scientific name.
8. Percent Cover: You will be assigning a percent cover measurement to each
species in a polygon. Remember that for a point, there is no area, so you will not
use a percent cover. For points, leave this field blank. For polygons, percent
cover is based on the total amount of cover the invasive species canopy
occupies in a patch. Canopy cover is determined by the total amount of ground
covered by invasive species vegetation in the patch when examining the patch
from an aerial view. Data categories are: <1%, 1-5%, 5-25%, 26-50%, 51-75%,
76-95%, 96-100%.
9. Notes: Use this field for any notes you need to take in the field. If possible, put
all notes related to that particular record in this note field. Since it can be
cumbersome to use the handheld keyboard for lengthy notes, you may want to
carry along a notebook to record notes in. Be sure to write down the auto id
number for each point and polygon you create notes for. When you upload your
data, you will have the opportunity to attach more notes to your file. When you
enter these notes in the computer, write the auto id number and designate point
or polygon next to the appropriate note so that they can be
matched with the correct species record.
10. Slope: Use the drop down menu to choose a slope
category (Flat, Gentle, Moderate, Steep, Cliff).
11. Aspect: Choose the direction your slope faces from the drop down list. You
only need to record aspect if you are on a hillside. While even gentle sloping
areas have an aspect, we are primarily interested in verifying that the GPS
coordinates show up on the correct side of a hill.
12. Distance to water – distance to road: Estimate the number of meters your site
is from the nearest water and road. You should choose the nearest edge of your
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invasive species patch when determining distance to water and road. You may
need to clarify your information in the Notes field. If you are nowhere near water
or roads, you can leave this field blank and mention it in your notes.
13. Vegetation types/ Water/Riparian Types/ Landform/Disturbance: These four
fields are for describing the ecosystem in which you are working. Choose a type
in the drop down menu in each of these fields based on the definitions in your
Invaders handbook.
14. Extent: In this field you will be
choosing isolated, localized, extensive,
or overrunning. These categories are
defined on the back of your datasheet.
These qualifiers should describe the
overall infestation. Look across the
landscape beyond the main part of the
invasive patch to determine the extent
of area the invasive species is
occupying.
15. Your Name: Record your name in this box. After you have typed it once, it will
appear in the drop down menu.
16. Soil Crust: If soil crusts are present at your point or polygon, you can choose
yes or you may type in a percent of the soil covered by these biological crusts. If
no soil crusts are present, choose no from the drop down menu.
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When you have completed all data fields, close the data entry window by touching the X
in the top right corner.
Step 7: Saving data.
It isn’t necessary to save your data after every point or polygon recorded but it should
be done every hour or so to prevent data loss should the battery fail.
To save data go to
 Layer → Save Layer → highlight the file you wish to save.
 Select the following
 Folder = None,
 Type = Map: SHP + SHX + DBF,
 Location = Storage Card
 Hit OK
 You must select what datum to store the file in
 Chose UTM, Zone 12 and from drop down select World WGS84
 Repeat this for the other layer (point or poly) if appropriate.
General Saving : Back-up to the removable memory card.
When collecting a lot of data it is important to periodically save to the flash memory.
This will prevent data loss in the event of battery failure or damage to the unit. To do
this tap: START/ Programs/ Sprite Backup.
It takes less than a minute to finish and will return you to the programs screen
automatically.
If you ever experience a hard reset on the unit you can restore your data from your last
backup by tapping: START/programs/ sprite backup/restore now
It will prompt you for permission to do a soft reset once complete.
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General Digital Camera Instructions
You may use your own personal camera or the cameras provided in
the ASDM Invaders field kit. For specific instructions on the
cameras provided in those kits, see those sections.
Digital images will be used to document your species observations. These photos will
be stored in the database along with the text and location data to allow a species expert
to verify your submission.
Before you leave
Ensure the camera memory card is blank. This will help prevent confusion about the
invasive species data to which this set of pictures belongs. You should also have a
fresh or fully charged set of batteries.
In the Field
You will need to take species photos when using your handheld PCs to verify your data
records. To make sure that the correct species are associated with the corresponding
photo, you will need to write notes in your field notebook. It will be critical to enter your
data as soon as possible after returning from the field so that your notes are still fresh in
your mind.
Species photos: Since you will be working with a large number of species, these photos
are crucial. Keep in mind our procedures for taking species photos including using
proper photography techniques (macro mode, proper background, lighting issues, etc. –
See more information on camera use in the equipment section) and photographing the
part of the plant that will best facilitate identification by our experts. You will also now
be taking multiple photos for each point and polygon if there are multiple species
recorded in it.
 Use the back of your notebook to photograph the plant part and the point or
polygon number with the letter a, b, c, d, or e corresponding with the 1st, 2nd, 3rd,
4th, and 5th species in that point or polygon (ex: PY1-A, PY1-B, etc.).
 In your notebook, write the photo number and letter followed by the name of the
species you believe it is. You will need this when you upload your photos during
data entry.
 If you feel that the photograph alone will not be enough to identify that particular
species, you should collect a specimen in a plastic bag (remember our rules for
transporting invasive species) and label the bag with the point or polygon number
and letter, the species name, your name, the park name, and the date.
 When you download your photos, you should rename the species photos to help
you in the upload process (ex: PY5B_brassica_tournefortii.jpg). If you go to
multiple parks in one day or have multiple park pictures on the same camera
card, you should use the naming scheme:
Ironwood_species_PY5B_brassica_tournefortii.jpg).
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Photo Tips
Ideally the sun will be at your back, but this may wash out the LCD screen on the
camera if your camera has one. In this case you may want to use the viewfinder
instead. Turning off the LCD screen will also extend battery life
When taking a close-up picture for species id, use the back of the clipboard as a solid
background. Do not use a white or black background to ensure better definition. Write
the record number on a sticky note or attached white board. It is essential that you can
associate the image with the correct plot when you are ready to enter your data on the
computer. It is unwise to rely solely on the camera’s automatically assigned image
name. The record number will aid in tying the image to your data collection sheets.
Overview of abundance
Close up of Species
If your close-up shot is less than ~40cm from the item you should use the Macro mode.
Don't use the digital zoom feature; it degrades image quality.
Getting the pictures off the camera
When you return from the field and are ready to enter your data, you will first need be
able to browse to your pictures with “My Computer”, “Windows Explorer” or the “Finder”
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Method 1
Connect the camera via a built in USB port to the computer.
When they are connected and you turn on the camera, your computer will
recognize it as another drive and allow you to view the pictures.
Note: this uses the camera’s batteries, so be sure to turn the camera off when
not in use.
Method 2
Take the card out of the camera an insert it into the card reader.
The reader plugs into a USB port on your computer. If your computer is Windows
2000 or XP, or Mac OS X, the reader will be automatically
recognized and show up as another drive.
For Windows 98 or ME, or Mac 9.x, you may need
software that is available from ASDM.
An image file will have a default name of “IMGP00xx.JPG”
If you have taken more than the required number of photos, you should select the best
ones prior to going on-line so the data entry process is not interrupted.
You should enter your data into the database as soon as possible after your field visit,
while the information is fresh in your mind. The image filename will be renamed to link it
to your specific survey information during the upload process.
Once you have entered your data and uploaded the pictures, be sure to reformat the
card in preparation for the next user or field survey.
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SPECIES VERIFICATION METHODOLOGY
Photos: You will need to take at least one and sometimes more photos at each
invasive species patch. These photos will allow an expert to verify your species record.
Sometimes one photo will be sufficient to identify a plant and other times you may have
to take a close up of an inflorescence as well as an overall plant photo. When you have
advanced to the EXPERT level for a particular species, you will no longer need to
include an identification photo for that species.
See the section on “Using the digital camera in the field”
for specific information on photo protocols and tips.
Specimen Collection: In some cases, it might be beneficial for
you to collect a specimen of the invasive plant. If a photo does
not correctly represent the species or if the plant lacks easily
identifiable characteristics such as reproductive structures or seeds, you should collect
a specimen to bring back to ASDM for verification of species. There are some specific
rules and protocols for collecting invasive species specimens.
1. Be aware of where you are collecting. On some lands, it may not be legal
for you to collect plant specimens without a permit. See the section on private and
public land research issues to learn more.
2. Always use a ziplock bag or tie off a larger bag when collecting specimens.
We do not want to spread the seeds of invasives during our collection efforts.
Carrying loose material across landscapes, in your vehicles, at your homes, or at
ASDM will allow them to spread more quickly.
3. Bags should be labeled with the date, your name, the site name and gps
coordinates or the auto id number and point or polygon designation. Also put the
name of the suspected species on the bag.
WHEN YOUR FIELD DAY IS COMPLETE
At the end of your data collection trip:

Make sure your data are saved and turn off your cameras, handheld computers, and
GPS units to save batteries. Store them in a safe place in your vehicle to protect
them from damage.

Before leaving the site, make sure to clean your socks and boots to make sure that
you are not transporting invasive plant seeds with you. This is something you
should do between sites as well.
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
Return the equipment and Resource Kit to ASDM and enter your data as soon as
possible. It is important to enter data promptly after field work in order to remember
details that will help you associate photos with corresponding data records.
Congratulations! You have collected scientific data and entered it into our database.
Your efforts as a citizen scientist will go a long way towards assisting managers and
scientists with the fight to “Stop the Spread” of invasive species in the Sonoran Desert
Region.
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INVADERS DEFINITIONS
VEGETATION TYPES
Chihuahuan Desert: Shrubby desert in southeastern AZ with no saguaros or palo
verdes (or any trees at all except in arroyos).
Mohave Desert: Shrubby desert in northwestern AZ with no saguaros or palo verdes.
Devoid of trees except for Joshua trees above 3000 feet. Below 3000 feet it is very
difficult to distinguish Mohave Desert from Lower Colorado River Valley Sonoran
Desert.
Arizona Upland Sonoran Desert: Rocky mountains and narrow valleys with saguaros
and foothill palo verdes growing on slopes.
Lower Colorado River Valley Sonoran Desert: Broad valleys and widely-spaced
mountains. Palo verdes and other trees grow only along drainages. Saguaros are
mostly on valley floors and lower bajadas, or may be absent.
Chaparral: Hilly terrain covered with impenetrable layer of shrubs (open after fires).
Interior chaparral is mostly shrub live oak and manzanita.
Coniferous forest: Conifers (pines, firs, spruce, etc.) are the dominant trees.
Oak Woodland: Open parklike landscape (tree canopies do not overlap). Land between
oak trees may be mostly grasses or shrubs.
Oak-pine woodland: Mixture of pines and oaks. In woodland tree canopies do not
overlap (there are sunny gaps between trees). If most trees are conifers and canopy is
nearly continuous, call it coniferous forest.
Grassland: Flat to rolling terrain dominated by grasses. There may be a fair number of
shrubs, yuccas, and chollas present (desert grassland). If there are more than a few oak
trees per acre, call it oak woodland.
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DEFINITIONS CONTINUED:
WATER/RIPARIAN TYPES
Marsh-oasis: Perennially wet lowland or palm canyon with water-loving plants.
Lake/reservoir: Natural or artificial body of permanent water.
Temporary water: Dries up part of the year, e.g., stock ponds filled by runoff, roadside
ditches.
Stream/river: Permanent or nearly-permanent flowing water (could be just below the
surface).
Spring: A small area where water is at the surface, permanent or seasonal. A larger
and permanent area of open water is an oasis or marsh.
LANDFORM
Ridgetop or mesa: A ridgetop is a narrow, linear mountaintop that falls off steeply on
both sides. A mesa (table) is a wide flat area on a summit.
Rocky slope: A steep hillside of exposed bedrock.
Rocky slope with cliff: Same but with a nearly vertical slope.
Rocky slope with talus: Talus is a layer of loose, unstable rock on a very steep slope.
Canyon: A steep-sided narrow cleft in the mountains. There may or may not be a
stream at the bottom.
Upper bajada: The upper portion of the outwash (alluvial) slope just below the bedrock
mountain slopes. An upper bajada has a distinct slope and the surface is usually rocky.
Lower bajada: The lower outwash slope between the upper bajada and valley floor.
The slope of a lower bajada is gentle to barely detectable, and the surface is usually
gravelly or silty.
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Definitions continued:
LANDFORM CONT’D:
Valley floor: Valley floors appear virtually flat and level to the eye.
Rocky or gravelly: Uncommon unless covered by a lava flow.
Sandy or silty: Fine-textured soils.
Floodplain: The first terrace above the stream channel that is flooded during
heavy streamflow times. Often support bosques of mesquites or saltcedars
and dense shrubs. Riparian trees may grow near the modern stream channel
or along old, cutoff channels.
Wash: A linear feature on bajadas or valley floors that carries water for brief periods
following heavy rains.
Shallow or no banks: Shallow sloping sides less than six feet tall, easy to climb
out of. Washes with no banks (no obvious channel) can be difficult to discern
except for a ribbon of denser or taller trees; best seen from above. No-bank
washes merge into sheet-flood areas near valley floors; distinguished by a broad
band of desert trees without clear outer boundaries.
Deep/steep banks: Steep sides more than six feet tall, difficult to climb out of.
Sand dunes or flats: Loose sand that can blow around in the wind. Dunes are obvious
and are nearly devoid of vegetation. Sand flats may have fairly dense vegetation that
impedes blowing sand.
DISTURBANCE
Recent fire: Revealed by sparse vegetation and evident charcoal.
Flood: Indicated by flattened and/or torn out vegetation; scouring of ground after severe
floods.
Cleared: Bulldozed or plowed; no mature woody vegetation.
Urbanized: aka Asphalt Scrub
Roadside: The area between the edge of the pavement and the limit of regular
maintenance, which is usually the right-of-way fence. Includes medians of divided
highways.
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SLOPE
Flat: Level or barely detectable slope.
Gentle: Slope apparent to eye, but little sensation of whether walking uphill or downhill.
Moderate: Definite slope; can tell if you ’re walking uphill or downhill, but not difficult to
walk.
Steep: Difficult to walk even short distance up or down.
Cliff: Nearly vertical slope that most people would not try to climb.
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DEFINITIONS CONTINUED:
PATCH TYPE
Point: A point can be a true point with one or a few plants, but it will also be used for
polygon patches that are less than 5m wide and not linear in nature. The general shape
(i.e. square, circle, oval, rectangle, etc.) and size should be given if point is the chosen
patch type.
Line: A linear patch of invasives that is <5m wide will be considered a line. A line need
not be straight, but can follow along meandering roads, trails, or washes. The width of
the linear patch on average should be given when line is chosen as the patch type.
Polygon: Except for a single plant, technically all patches will be polygons. For
purposes of these invasive species protocols, a polygon will be any patch larger than
5m wide of any shape. When a patch is designated as a polygon, the general shape of
the patch should be given on the data sheet.
EXTENT
Isolated: No other specimens visible beyond plot.
Localized: Other specimens or few patches beyond plot.
Extensive: Many more plants/patches visible, but not dominating landscape.
Overrunning: Weed is abundant/dominant over widespread area.
PERCENT COVER
Percent cover is the estimated amount of ground covered by the vegetation of the
targeted species when viewing the patch from an aerial position.
Categories are: <1%, 1-5%, 5-25%, 26-50%, 51-75%, 76-95%, 96-100%.
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PUBLIC AND PRIVATE LAND ISSUES
The goal of the Invaders of the Sonoran Desert Region Program is to have many eyes
and ears detecting and reporting invaders in as many places as possible. However, we
have to be mindful of both public land rules and regulations and the rights of private
landowners.
Public Land
Some agencies do have very strict rules concerning collection of data and specimens
and require permissions. The National Park Service requires permission for these
activities and we are working with local parks to create partnerships for this program.
Arizona State Trust Land, Arizona State Parks, and USFWS Refuges are examples of
other lands subject to permits as well. The ASDM Invaders Team is working with local,
state, and federal agencies to forge these partnerships for this Program. When in doubt
about the public ownership of a property you plan to survey or the rules of that particular
agency, contact a member of the Invaders Team for more information.
Private Land
It is important that we respect the rights of private landowners and do not trespass on
their land without their specific permission. Keep in mind that Public Rights of Ways
(ROW) like roads are not considered private land. Many of your surveys will be along
these ROWs. This handbook includes a letter that you can present to landowners or
the public should you receive inquiries while doing your fieldwork. This letter expresses
assurance that our research project will not be conducted on their private property
without their express permission and summarizes the goals and purpose of the Invaders
of the Sonoran Desert Region Program.
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Invaders of the Sonoran Desert Region
January, 2007
To Whom It May Concern,
The holder of this letter is a volunteer citizen scientist working on behalf of the Arizona-Sonora
Desert Museum’s Invaders of the Sonoran Desert Region program. He/she is helping to track the
distribution of invasive species of plants and animals in our region. Invasive species are
organisms that are non-native to the ecosystem in consideration and cause or are likely to cause
economic or environmental harm or harm to human health.
The volunteers have been trained in identification and field techniques and have been provided
with a set of equipment to collect data on particular species’ locations and abundance and the
environmental conditions in which they are found. They are monitoring areas designated by the
Invaders Program and using protocols that will help paint a picture of invasive species spread in
both urban and wild land areas.
Once volunteers have completed field surveys, their data will be uploaded to a web-based
database and made available to resource management entities and the general public. Their
investigations are part of a national effort to map target invasive species and assist land managers
in their control and eradication. You can find out more at www.desertmuseum.org/invaders. Feel
free to contact the Invaders program coordinators listed below if you have further questions.
Thank you,
The Invaders Program Team
Tani Hubbard
Invaders Program Manager
Arizona-Sonora Desert Museum
2021 N. Kinney Rd.
Tucson, AZ 85743
(520) 883-1380 ext. 133
thubbard@desertmuseum.org
Yajaira Gray
Invaders Program Volunteer Coordinator
Arizona-Sonora Desert Museum
2021 N. Kinney Rd.
Tucson, AZ 85743
(520) 883ygray@desertmuseum.org
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RED IMPORTED FIRE ANT
DATA COLLECTION PROTOCOL
Where is your site?
We will be sending you out to specific locations to collect data per requests from the
Arizona Department of Agriculture. These locations will likely be plant nurseries and
public gardens, but may also include truck stops, parking lots, warehouse sites, golf
courses, and parks.
Red imported fire ants require a permanent water supply and
shelter from extreme temperatures. When you are surveying a
site, extra care should be taken to survey an entire area,
especially around asphalt roads and cement pads, pallets,
bricks, mulch and edges of plastic tarps, or weed barriers. The
ASDM Invaders Team will provide extra on-site training when
we begin doing these surveys.
When will we be surveying?
Red imported fire ants can be surveyed from spring through fall. They are only inactive
in the colder winter months. We will be alerting all volunteers when we begin these
surveys and those interested will be provided an additional training prior to commencing
surveys.
What do I need to bring to the field?
We will put together field kit materials for these surveys that
will include empty film containers with lids, bait (bags of potato
chips), surveyor flags, name and sample labels, plastic bags,
clipboards, sharpies, paper, pens and pencils, and ice chests
for samples.
Working in Groups
When you are sent out to survey a site, you will work in groups of at least 4 to be able to
complete the survey in a timely manner.
Data Collection
Sites should be surveyed prior to the temperature reaching 100º F. During summer
months, surveys should begin by 6 am in order to complete the task in time.
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1. One person on the team will be assigned the task of supervising the project and
laying out the general grid for the others to place flags and bait and collect
samples. This team leader will also be responsible for setting up the labeling
scheme for the sites and will work with other members of the team to assure that
samples are labeled properly. Upon arriving at a survey site, the team leader
should make contact with site personnel (i.e. nursery managers, property
owners, etc.) to coordinate the activities.
2. Once it has been determined how the site will be laid out, flags should be placed
in the ground no less than 20 ft apart in a grid across the site (flags can lay on
the ground sticking out of a film container if the ground is too hard).
3. Place a film container, with the lid removed, at each flag. Each film container
should have bait (potato chips) inside and be laid on its side for easy ant entry.
4. Wait approximately ½ to 1 hour after placing all bait stations. If you wait too long,
ants often feed and then disappear, especially if it gets hot out. It is best to start
collecting sooner, rather than later, but if still cool, wait until it warms up and ants
begin foraging.
5. Remove bait containers, bait, and flags where no ants are found.
6. When ants are found in the bait containers, collect the ants by placing a cap on
the container. Place a label with the sample number written in sharpie pen on all
sample containers. Place all samples in plastic sealable bags and put them in
the ice chest. Multiple samples can be placed in the same bags. Make sure that
container lids are secure and will not come off during transport.
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7. Before leaving the field site, ensure that all flags, bait, containers, and any other
materials are removed from the area. Be respectful of the needs and concerns
of the site manager or owner.
8. Bring all samples back to ASDM and put in a refrigerator or freezer. If you
cannot go back to ASDM that day, you may put them in your refrigerator or
freezer at home and bring them to ASDM at your earliest convenience.
What happens to the samples now?
Robin Kropp and Tani Hubbard will be providing the initial screening of the ant samples
at ASDM using microscopes. When they find samples they believe may be red
imported fire ants, those samples will be packaged, labeled, and mailed to the Arizona
Department of Agriculture for a taxonomist to verify. If red imported fire ants are
verified, the Department of Agriculture will revisit that site to determine the extent of the
infestation and then will apply control measures to eradicate the animals from the site.
So far, the Arizona Department of Agriculture has been 100% successful at eradicating
all red imported fire ant infestations in the State of Arizona. As an Invaders volunteer
you will be assisting them with keeping a perfect record.
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ARGENTINE CACTUS MOTH
SURVEY PROTOCOL
TRAP SET UP
1. One wing-trap will be set up at each site (nursery). Wing-traps will either hang
from a tree near prickly pear plants or will sit on top of a pole when a tree is not
available. We will choose sites together at each nursery.
2. At each site, complete the top section of the data sheet designated for
that location. This includes the name of the nursery or garden, the
contact person and telephone number, the date the trap was first
installed, the temperature, the humidity, the name of the citizen scientist
setting up the trap and the GPS coordinates.
3. Fill out the Site note sheet on the inside of the Site Folder. Take photos of the
trap and its location.
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4. If the nursery or garden has a thermometer and hygrometer in an accessible
location, you may use that information for the data sheet. Otherwise, you may
just take the temperature with an ASDM or your own thermometer.
5. Set up a wing-trap and record the site name and date on the sticky plate. Attach
the trap to the tree or pole. Attach the pheromone lure with a pushpin into the
trap. Do not touch the lure with your fingers. Make sure the lure is all the way on
the pushpin. Check that the trap is secure.
TRAP MONITORING (MAKE SURE YOU BRING A THERMOMETER, NEW STICKY
TRAPS, FRESH LURES, AND THE SITE FOLDER)
1. When you arrive at a site for monitoring, first announce your arrival to the site
contact person or to whoever is in charge that day. Let them know how long you
will be there and what you are doing if you have not met that person
before.
2. Remove the sticky part of the wing-trap, fold over, and secure with a
rubber band. Attach a new sticky plate with the site name and date
written on it. Remove the old pheromone lure and replace it with a
fresh one. Do not touch the lure with your fingers. Hang the trap back up or
place it back on the pole. Make sure the
trap is secure.
3. If any other part of the trap needs replacing
or there are any other problems, contact
Robin or Tani.
4. Complete cactus moth data sheet including monitoring date and time,
temperature and humidity, your name, and any notes. Check off the boxes under
lure changed and trap collected when you have completed that. For each site
visit, you will be filling out one full row on the data sheet.
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5. Return all traps and site folders to the Desert Museum. Make sure that all traps
collected are labeled properly and folded and secured so that they don’t get
crushed. Traps should be placed in the designated refrigerator or freezer.
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Invaders of the Sonoran Desert Region
Early Detection and Reporting Data Sheet
Cactus Moth
Site Name:______________________________ Site Contact: _________________________ Phone: _________________
Setup Date: _______________ Temperature: ______ Humidity: ______ Setup Researcher Name(s): ___________________
GPS coord: Lat-N ______ ° _______min ________ sec
Lure
DATE
Time
Temp. Humidity Changed
Long-W ______ ° _______min ________ sec
Trap
Collected/ NOTES
Replaced
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Monitoring
Researcher(s)
Name
Lure
DATE
Time
Temp. Humidity Changed
Trap
Collected/ NOTES
Replaced
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Researcher(s)
Name
5
Data Entry Guide
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DATA ENTRY PROTOCOL
Download Files from your Handheld PC
When you plug the PDA into a USB port, you will be prompted to set up a
partnership. Select “Guest Partnership” then click on Next
Click Explore to open a File management window. Then copy your files from
Mobile Device to your hard drive (in the library, this will be “c:\invaders\gis\your
name”). INVADERS volunteers working on this project will each have a folder
with their name on it. You will save your files in your own folder.
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Download Photos from your Camera
Plug your camera into your computer and download your images as you have
done before. Save your images on the hard drive (in the library, this will be
“c:\invaders\gis\your name”). INVADERS volunteers working on this project will
each have a folder with their name on it. You will save your files in your own
folder.
You should rename your photos to help you in the data submission process.
Photos could use the designation: PY5B_brassica_tournefortii.jpg. If you go to
multiple parks in one day or have multiple park pictures on the same camera
card, you could use the naming scheme:
Ironwood_PY5B_brassica_tournefortii.jpg. If you take multiple photos you can
use numbers (ex: PY5B_brassica_tournefortii_1.jpg;
PY5B_brassica_tournefortii_2.jpg; etc.). Remember that you may have up to 5
species per polygon so it is important to designate which species record you are
referring to (i.e. PY5A, PY5B, PY5C, etc.).
You may use your own naming scheme as long as it is clear what point or
polygon the photo belongs to, and a species name. These will all help you
tremendously when you are uploading many photos in the data entry process.
Upload Files
1. Log in to the INVADERS web site.
2. Choose “Submit New Handheld PC Data.” This will bring you to the page
titled, “Handheld PC Data Submission.”
3. Your name should show at the top of the general information box. Put
your field notes in the Survey Notes box and fill in the location field. It is
very important that you do not leave the location field blank. This field is
crucial for the transfer of data to our partners.
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4. In the Survey File Upload box, choose Poly or Point. You will upload your
three files associated with the point or polygon file you created in the field
(dbf, shp, shx). Browse to those files to add them in.
5. After you have verified that you have put the correct data files, click on
CONTINUE to go to the Photo upload page.
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Photo Files
1. You should now see the web page with the title, “Handheld PC Data
Submission – Page 2.” The details from page one should be listed there
along with an ID # assigned to the point or poly files you uploaded.
2. Now you will add identification photos that go with the point or polygon file
you just uploaded on page one. You will be entering many photos with
each point or polygon file since there are multiple points and polygons
within those files. You will be using your notes again to make sure that all
of the photo files are uploaded. This is where renaming photos when you
download them from your camera is very important.
 For each photo, enter the point or polygon ID # of the photo you are
entering. Select a species. Click UPLOAD PHOTO once you are sure
that you entered the correct information.
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 Now you should be on Page 3 of your submission and the photo file
you just uploaded is listed in the”Submitted Photo Details” box at the
top of the page.
 Now you have the option of uploading more handheld PC files or
adding another photo below. You should add all of the photos
associated with the point or polygon file you uploaded on page one
before going on to enter another point or polygon file.
 After you have all of your photos uploaded, review the list to ensure
that all the photos are listed and the information is correct.
 When you are finished, you can go back and upload more handheld
PC files, or you can return to the login/logout page to exit the
INVADERS web site.
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WHAT HAPPENS TO YOUR DATA NOW?
Now that you have successfully entered your data into the web-based data entry
form your data will be verified at ASDM and then submitted into a national USGS
database and made available to all managers and scientists who work to
monitor, control, and eradicate invasive species.
DATA VERIFICATION AT ASDM
Until you reach the “Expert” level, ASDM and partner scientists will verify your
data records and species identification. This will be done using the photographs
that you upload to your data record and the specimens that you collect. ASDM
will use the data and GPS coordinates in-house for ongoing conservation and
mapping projects.
NATIONAL DATABASE
When your data reaches the national database, USGS staff will create dynamic
maps of the infestations using a Geographic Information System (GIS). These
maps will be available online for managers, scientists, and others working with
invasive species. Users will also be able to query the database for specific
information and view landscape photographs from your site. Your name as the
scientist will be attached to each record and will be available to all who are
interested in using your data.
LOCAL AND REGIONAL PARTNERS
ASDM staff are developing partnerships with other Sonoran Desert region
agencies and organizations. Partners will create and send us lists of target sites
for Early Detection and Reporting. Your data on these target sites will be sent to
these partners who will then be able to make more informed decisions when
creating management strategies including plans for prevention, control, and
eradication. Managers may use your data to find areas that need more intense
surveys or they may query the database to check the status of areas that
previously underwent eradication.
If you become involved in local eradication programs, you may even find
yourself using the data you collected to target new areas for control and to
determine success of your own eradication efforts!!
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