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Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD
RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
Emily Massey
My interest in orchids began when I was an undergraduate student at Illinois College
(IC), a small liberal arts institution located in Jacksonville, Illinois. There, I worked with Dr.
Lawrence Zettler in the Orchid Recovery Program. This program focuses on the propagation,
study, and reintroduction of threatened and endangered orchid species. While at IC, I
participated in a number of studies with several different orchids. These projects included two
studies involving symbiotic seed germination. In the first study, we examined crossing effects
on seed viability, germination, and protocorm growth in Platanthera leucophaea (Nuttall)
Lindley, the eastern prairie fringe orchid. Seed germination, propagation, and reintroduction
of Epidendrum nocturnum Jacquin, the night-fragrant epidendrum was examined in our
second study (Massey et al., 2007). I also participated in a study to asymbiotically propagate
several epiphytic south Florida orchids such as E. amphistomum A. Richard, the dingyflowered star orchid; E. rigidum Jacquin, the rigid epidendrum; Polystachya concreta (Jaquin)
Garay & Sweet, the yellow helmet orchid; Prosthechea cochleata (Linnaeus) W.E. Higgins var.
triandra (Ames), the Florida clamshell orchid; and Vanilla
phaeantha Reichenbach f., the oblong-leaved vanilla
orchid.
Fig. 1 Image of me and the two
other students (William Kutosky,
and Kris McDonald) reintroducing
E. nocturnum at the Florida Panther
National Wildlife Refuge in 2005
All of these studies were conducted in the
laboratory, except for the reintroduction of Epidendrum
nocturnum, which is an endangered Florida epiphyte with
night fragrant flowers that are believed to be pollinated by a
species of hawkmoth. Although I liked lab work, it was this
study that introduced me to field research and it was one of
the best experiences I had while working with Dr. Zettler.
The project took place in the fall of 2005 at the Florida
Panther National Wildlife Refuge (FPNWR). The FPNWR
is located 20 miles east of Naples in Collier County,
Florida and was established as a safe haven for the
diminishing Florida panther population and other
threatened and endangered animal and plant species.
S.L. Stewart
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Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
For about a week, two of my lab mates and I visited the refuge to reintroduce
Epidendrum nocturnum seedlings propagated in our lab. At the time of the reintroduction, the
cool, murky water at most sites was waist and chest deep for my 5’2’’ stature (Fig. 1). You
definitely had to be careful where you were walking, or I should say feel around where you
were stepping, because you sure could not see through the water beneath your feet. This was
due to the presence of tannins that darken the water into a coffee-like brew. This was a very
Fig. 2. One of the many swamp buggies in the fleet.
intimidating project and I was a little apprehensive at first. We were venturing out into the
wilderness, with the possibility of running into an alligator or worse, and we were on foot.
However, the longer we worked, the less this seemed to matter. I may have had to wring out
my clothes every night of the trip, but this field research experience was one of the most
memorable moments of my life. I had many other new experiences as well. I got to take my
first spin in a swamp buggy, which is basically a very large, open-air vehicle resembling a
monster truck without a top (Fig. 2).
Another new experience and probably one of the more amusing moments of this
excursion took place when a local news reporter and cameraman came out to the refuge to
capture our efforts. The cameraman must have known what he was getting into because he
showed up wearing boots and worn clothing. Perhaps the reporter should have consulted
with him before he dressed that morning because he wore shiny dress shoes, khaki pants, a
very neat button down shirt, and a tie. Needless to say the reporter was a bit out of his
element, but he was a good sport about it. With a smile, he waded out into the swampy water
32
Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
after a few minor wardrobe adjustments (i.e., rolled up his pant legs a good three or four
inches and donned a pair of borrowed boots) to film a portion of the piece.
We eventually reintroduced 43 Epidendrum nocturnum seedlings back into the wild.
Unfortunately, this part of Florida had just been damaged by Hurricane Wilma. This stripped
many of the trees’ upper canopy, exposing the seedlings to higher light levels and fewer than
10%
of
our
reintroduced seedlings
remained one year later.
Another issue was that
we had little idea of
what trees to affix these
seedlings and what
microhabitat conditions
they
needed
(i.e.,
epiphytic
assoc-iates,
location on the tree, and
the
light
levels
required). The locations
we selected for these
plants were based on
observations made by
the staff at the refuge
and students performing
research on site. The
FPNWR is home to about 27 orchid species in 17 genera with many of these species being
threatened or endanger-ed. It is possible that the survival of many of these species hinges on
the habitat (i.e., tree species in the area), the microhabitat (i.e., substrate of establishment and
epiphytic associates), and other factors (i.e., light level to which they are exposed). However,
little to no data has been collected on the orchid microhabitats of these species at the refuge.
Fig. 3. Image of one transect at the study site.
This leads us to the study at hand. My project surveyed an area of the FPNWR for
epiphytic orchids and the mircohabitats associated with them. The site was classified as a
slough transitioning to a floodplain swamp and was believed to consist mainly of pop ash
(Fraxinus caroliniana), pond apple (Annona glabra), and baldcypress (Taxodium distichum) for
epiphytic orchids and catalogued the microhabitats associated with them. Some of the species
I surveyed were orchids that I had worked with in the Orchid Recovery Program back in
Illinois. Again, I was working in some of the same sites I had visited two years ago, but the
terrain was slightly different. For one, the atmosphere was very different. The cooler fall
weather had been replaced by the hot and very humid summer months. The site was no
longer flooded and I could see where I was stepping most of the time. Despite this, I still
encountered some obstacles. About once a week, I experienced tiny paper cuts on my exposed
arms and legs, cuts that were the direct result of the very tall and sharp saw-grass (Cladium
33
3
Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
jamaicense), which in some spots was taller than me. The saw-grass was also an area of concern
because alligators often find this habitat to be conducive for nest building. I encountered
many more mosquitoes than I had in the fall and began each day by spraying myself with bug
spray. Fortunately the only animals I came across were deer and a couple of harmless snakes.
The data were collected in June and July of 2007 by another student, Cabrina
Hamilton, and me. Data were collected for this project along 30 transects, 140 m long and 10
m apart for a total area sampled of 42,000 m2 (Fig. 3). An orchid was counted in the survey if
it was within 1 meter from the ground (Fig. 4). A midday light measurement was also
collected for each plant using a Sper Scientific, Broad Range LUX/FC meter (840022) and
recorded in Lux. Some other data collected consisted of the phorophyte (i.e., a plant on which
epiphytes grow) for each orchid, the substrate on which the orchid was established (i.e., moss,
bark of host tree, lichens, or a combination of any two), the diameter of the part of the tree
closest to the orchid was measured in centimeters, and the orientation of the orchid in regards
to substrate tilt (i.e., located on the trunk, an angled or a horizontal limb, or on a fallen tree)
along with the directionality of the orchid (i.e., facing N, E, W, S, NE, NW, SE, and SW).
The orchid’s epiphytic associates were measured (i.e., vascular plants like bromeliads and ferns
and non-vascular organisms like lichens and mosses). We also subjectively determined the
percentage of the area in the microhabitat they comprised and estimated the number of
species present.
4
5
6
7
Figs. 4-7. Mature orchids sampled at the survey site. Campylocentrum pachyrrhizum is an example of a
leafless orchid [5], Prosthechea cochleata var. triandra an orchid with leaves and visible pseudobulbs [6],
and Epidendrum amphistomum an orchid with leaves and no visible pseudobulbs [7].
34
Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
8
9
Figs. 8, 9. Mature orchids in flower during the study: Epidendrum amphistomum [8] and Polystachya concreta [9].
The orchids themselves were divided into three categories based on their
morphological differences: leafless (Fig. 5) (i.e., Campylocentrum pachyrrhizum (Reichenbach
f.) Rolfe, crooked-spur orchid; ribbon orchid and Harrisella porrecta (Reichenbach f.)
Fawcett & Rendle, the leafless harrisella), orchids with leaves and visible pseudobulbs (Fig. 6)
(i.e., Encyclia tampensis (Lindley) Small, the Florida butterfly orchid; P. concreta; and P.
cochleata var. triandra), and orchids with leaves and no visible pseudobulbs (Fig. 7) (i.e.,
7
8 E. rigidum). They were further subdivided 9into
6Epidendrum amphistomum, E. nocturnum, and
their stages of development. The plants without leaves were separated by the number of green
roots: seedlings (>3 green roots), juveniles (3-5 green roots), and mature plants (with
flowering or fruiting bodies or >5 green roots). The plants with leaves were separated into
seedling (plant ≤0.5 cm), juvenile (plant ≥0.5 cm and ≤10 cm), and mature (flowering or
fruiting bodies or plant ≥10 cm) plants. The number of green roots (leafless orchids) and the
number5of green leaves were counted (orchids with leaves). If a plant was in flower or fruiting,
7
then we also counted the number of flowers and capsules. During the study the only orchids
in flower were E. amphistomum (Fig. 8) and P. concreta (Fig. 9) and the only orchid seen in
fruit was E. amphistomum.
We sampled 419 orchids in total with a majority of the orchids surveyed being
juveniles with fewer mature plants and seedlings. Of the mature plants, E. amphistomum were
fruiting (2) and flowering (7). Polystachya concreta was also in flower (1). Most of the orchids
surveyed were found on pop ash (Fraxinus caroliniana) (371) with 100%, 89%, and 88% of
them being leafless, leaves with pseudobulbs, and leaves without pseudobulbs respectively.
Leafless orchids were observed on trunks or branches <51 cm in diameter whereas orchids
with leaves and visible pseudobulbs, as well as orchids with leaves and no visible pseudobulbs
were noted on trunks and branches between 11-110 cm. All of the seedlings sampled occurred
on moss, and it appeared that the juvenile and mature plants were either on moss or a
combination of moss and bark. A majority of the epiphytic orchids without leaves were
found on horizontal substrates, whereas orchids with leaves were affixed to branches/trunks
at a 45 degree angle or a vertical position. Moreover, the majority of the orchids were oriented
4
8
9
35
Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
on substrates that received little direct sunlight (N, NE position). Many of the epiphytic
associates consisted of mosses and ferns (e.g., resurrection fern, Pleopeltis spp.), as well as
bromeliads, vines and occasionally lichens (Massey et. al., 2008).
Taken together, it appears the orchids at this site are established on moss or a
combination of moss and bark of the phorophyte, which is largely pop ash (F. caroliniana)
with all of the seedlings being established on moss. These orchids were often facing in a
northerly or northeasterly direction and either on branches or trunks tilted at an angle or
vertical for the orchids with leaves and horizontal for the leafless orchids.
Currently, the Orchid Recovery Program at Illinois College is propagating many of
the orchid species surveyed in this study with the hopes of reintroducing them. Despite the
thoroughness of this study, more research is needed before we can give orchids reintroduced
in this area a fighting chance. For instance, the data in this study seem to indicate that the
epiphytic orchids grow prominently on pop ash (F. caroliniana). We are unsure if this result is
due to there being more trees of this species in the area or if there is a physical (i.e., bark
texture, moisture capabilities, or the arrangement of the canopy cover) or chemical association
between the orchids surveyed and this species of tree. A future study could survey the trees in
this area or analyze the bark of all of the species of trees indicated in this study to better
understand this relationship. Also it seemed that despite the orchids growing in close
proximity to lichens few of them were established on or very close to lichens. Perhaps there is
a reason for this dissociation. I suggest further studying of the orientation and tilt for these
and other orchid species and more data collection of the phorophytes and branch diameter,
especially for the orchids with leaves. In addition to these factors, studies regarding the stage
of the orchid best suited for reintroduction should be assessed. Our data indicate that juveniles
(i.e., plant ≥0.5 cm and ≤10 cm) were highly abundant at the site so perhaps plants should
only be reintroduced if they are at a juvenile or mature plant stage.
Further study of these threatened and endangered orchids is needed. Many of these
species are in danger of being poached, having their habitats destroyed by humans and
hurricanes, and having their territory encroached upon by exotic species. Hopefully, this
study will promote future research aimed at improving the survival of both Florida orchids
and other threatened and endangered species through reintroduction or better protection and
management of their habitats.
Acknowledgements
Many people were influential from the conception of this study to completion of this manuscript.
Cabrina Hamilton for her aid in data collection, Dr. Lawrence Zettler for asking me to join his lab and fostering
my love of research, Larry Richardson and the U.S. Fish and Wildlife Service for allowing me to come and work
on the Florida Panther Refuge, Dr. Scott Stewart for helping with the formation of the study, Illinois College
and the Charles and Dorothy Frank Scholarship for funding my study, Dr. Elizabeth Rellinger for her all of her
patience in helping me with statistical analysis, the refuge staff for their assistance during the survey, and for
everyone who spent their precious time reviewing this article. I kindly thank all of them for their support.
36
Massey: AN UNDERGRADUATE’S FIRST ADVENTURE INTO FIELD RESEARCH:
AN EPIPHYTIC ORCHID SURVEY IN SOUTHERN FLORIDA
NANOJ 16(1): 31-37. 2010
Emily Massey, Department of Environmental Horticulture, University of Florida, PO Box 110675,
Gainesville, FL, 32611. [email protected]
As for my future plans, this study was a great experience and while I still enjoy laboratory work, it really
sparked my interest in field research too. Currently, I am a graduate student enrolled at the University of Florida
earning my Master’s degree in Environmental Horticulture. My proposed project examines water relationships,
specifically the affects of stress, and growth in two tree species. Although this is not based in ecological
restoration, this study will provide a good basis for future research. Eventually I plan on returning to more
ecologically based projects and securing a research position.
Literature Cited:
Massey, E.E., K. Hamilton, S.L. Stewart, L.W. Richardson, and L.W. Zettler. 2008. Substrate preferences of
epiphytic orchids (seedlings, juveniles, mature plants) within the Florida Panther National Wildlife
Refuge. Illinois State Academy of Science 101: 62-63.
Massey, E.E. and L.W. Zettler. 2007. An expanded role for in vitro symbiotic seed germination as a conservation
tool: Two case studies in North America (Platanthera leucophaea and Epidendrum nocturnum).
Lankesteriana 7(1-2): 303-08.
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