Nursery Pest Management Calendar

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Nursery Pest
Management Calendar
Kris Braman
University of Georgia
The Nursery Pest Management
Calendar
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Provides optimal scouting and treatment timing for
more than two dozen key insect and mite pests of
nursery plants
Provides a pest identification guide and discusses
biology and management
Is organized by major plant groups and by individual
pest or pest group
Provides an identification guide for beneficial insects
in the nursery
Updated chemical control options can be found at
CAES web site http://www.ent.uga.edu/pmh/
Nursery Pest Management Calendar
Plants
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Azalea/Rhododendron
Boxwood
Butterfly bush
Camelia
Coreopsis
Columbine
Crapemyrtle
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Dogwood
Gardenia
Holly
Juniper
Lantana
Maple
Oak
Oenothera
Pests in the Calendar
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Azalea lace bug
Azalea leaf miner
Southern red mite
Cranberry rootworm
Strawberry rootworm
Azalea bark scale
Azalea caterpillar
Boxwood leafminer
Boxwood psyllid
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Two spotted spider mite
Tea scale
Altica flea beetles
Japanese beetles
Asian ambrosia beetle
Dogwood borer
Cottony maple scale
Dogwood twig borer
Dogwood clubgall midge
Pests in the Calendar
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Citrus whitefly
Cottony cushion scale
Holly leafminer
Euonymus scale
Florida wax scale
Two lined spittlebug
Spruce spider mite
Two spotted spider mite
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Juniper scale
Flat headed apple tree
borer
Aphids
Orange striped
oakworm
Obscure scale
Lecanium scale
Maple bladder gall
Key Pests of Azalea/Rhododendron
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Azalea lace bug
Azalea leaf miner
Southern red mite
Cranberry rootworm
Strawberry rootworm
Azalea bark scale
Azalea caterpillar
Azalea Lace Bug (Stephanitis pyrioides)
Azalea lace bug adult
Azalea lace bug eggs
Azalea Lace Bug (Stephanitis
pyrioides)
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Adults are 1/8 inch long. The transparent wings are held flat on the back.
Their wings are lacy with two grayish-brown cross-bands connected in the
middle. Nymphs are mostly black and spiny. The flask-shaped eggs are
partially embedded in leaf tissue and often are covered with a black tar-like
secretion. There are four generations a year. Eggs overwinter in leaf tissue.
Lace bug adults and nymphs live and feed on the underside of leaves.
Scout for eggs in February and look for the first signs of damage on plants
in full sun or in protected areas beginning in March and continuing
throughout the summer. Look for white stippling on older leaves. Turn
stippled leaves over to find lace bug stages and black fecal spots. Examine
lace bug eggs with a hand lens for signs of parasitism (a round hole in the
top of the egg) and look for predators.
Time insecticide applications for the presence of the first generation
nymphs
Parasitic wasp that attacks and kills
lace bug eggs
Mymarid wasp next to
An azalea leaf hair
Parasitized lace bug egg
next to leaf midrib. Wasp
has chewed a circular
hole in the lace bug egg
and emerged
Azalea plant bug adult and nymph,
a predator that feeds on lace bugs,
thrips, other small insects
and pollen
Southern Red Mite (Oligonychus ilicis)
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Adults are ½ mm long, oval, purplish, or reddish, with eight legs. The red
eggs overwinter on the undersides of leaves. There are several generations
each year. Most activity occurs in spring and fall.
This imported spider mite has a wide host range, but prefers broad-leaved
evergreens in the Ericaceae and Aquifoliaceae. It is common on azalea,
camelia, rhododendron, mountain laurel, holly, rose, viburnum, firethorn,
and yew.
Examine plants closely for signs of stippling and the various mite stages on
the lower and upper leaf surfaces of broadleaved evergreens in early spring
and the fall. When stippling is noticed, tap leaves over white paper to
dislodge and count mites, as well as the beneficial insects and predaceous
mites. Predaceous mites have longer legs than the southern red mite and
move much faster. Look for red overwintering eggs on the lower surface of
leaves from November through early spring.
Application of a dormant oil to the lower surface of leaves when
overwintering eggs are numerous will help reduce spring populations. In
light infestations, the use of a horticultural oil or insecticidal soap will
control these mites with minimal impact on beneficial organisms. When
heavy infestations of mites are present, the application of residual miticides
often is necessary
Southern Red Mite
Azalea Leafminer (Caloptilia
azaleella)
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Adult moths are about 3/8 inch long with wings folded. They are
yellowish brown with purple markings on the wings and stand at a
60 angle when at rest. Mature larvae are about ½ inch long and
yellowish brown. There are two generations a year. Pupae
overwinter in leaf mines (tunnels the larvae create when they feed
on tissue between leaf surfaces). Look for blotch mines in April or
May. Curled leaf tips in June indicate completion of the first
generation. Second generation blotch mines begin in July. Shake
plants in late June and August to make adults fly and to estimate
their numbers. Treat in May if numerous developing blotch mines
are observed. Evaluate the second generation in July and retreat if
needed.
Azalea Leafminer (Caloptilia
azaleella)
Azalea bark scale
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Plants may appear
yellow and covered
with black sooty mold
insects on twigs
appear cottony or
waxy
Treat crawlers in late
April-May
prune out infested
plant parts
Azalea caterpillar
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Red to brown with
white and yellow stripes
when small
full grown have a red
head and prolegs with
white stripes
chemical control most
effective on small
caterpillars
Cranberry rootworm
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Small shiny black-green
beetles
Feed at night and hide
in litter during day
Remove litter and
weeds from area
Usually most common
in dense shade
Typically a Spring pest
Strawberry Rootworm
Strawberry rootworm, Paria
fragariae
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The strawberry rootworm, Paria fragariae, is a
pest of azaleas in production nurseries.
Damage from the adult results in holes in the
leaves which are unsightly. Current control
methods include spraying the foliage to control
adults with chlorpyrifos or carbaryl and
drenching the pots to control larvae with
acephate or bifenthrin.
Key Pests of Boxwood
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Boxwood leafminer
Two spotted spider mite
Boxwood psyllid
Indian wax scale
European fruit lecanium
Armored scales (greedy, oleander, oystershell)
Twospotted Spider Mite (Tretranychus
urticae)
Twospotted Spider Mite (Tretranychus
urticae)
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Adults are about 1/7 mm long, a little larger than a period on a page. They have one
oval body segment with eight legs. They are greenish-yellow with a black spot on
each side of the body. Eggs are white to yellow. Reddish-orange adult females
overwinter in bark cracks.
Spider mites have a very broad host range. They feed on conifers (see spruce spider
mite on Juniper), deciduous trees and shrubs, as well as herbaceous plants.
Spider mites suck leaf juices, causing minute white-to-yellow stipples to appear.
When large spider mite populations feed, the stipples coalesce and leaves may turn
white to yellow to grayish-brown and then die. Some plants are particularly
susceptible to spider mite toxins, and even low populations may cause leaves to die.
Look for early signs of stippling with the beginning of hot summer weather.
Examine the underside of damaged leaves or tap them over white paper and look
for spider mites with two spots on the body. Also look for predators, such as
phytoseiid mites and lady beetles, and note their relative abundance in relation to
the number of mites present.
In dry, hot, sunny locations, this spider mite may produce one generation a week.
Use horticultural oil or insecticidal soap sprays for low mite populations to
conserve any beneficials present. When damage becomes objectionable, mite
populations are high, and there are not beneficials, consider using a residual
miticide spray. Reevaluate in one week
Key Pests of Buddleia
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Two spotted spider mite
Two spotted spider mite
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37 Buddleia species and
cultivars evaluated
B. fallowiana ‘Alba’ and
B. davidii x B.
fallowiana ‘Cornwall
Blue’ highly resistant to
mites
Key Pests of Camelia
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Tea Scale
Southern Red Mite
Tea scale
Scale on camelia
Key Pests of Coreopsis
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Leaf beetles, Phaedon desotonis
These beetles are late winter through spring
pests. Beetles can build up large numbers
before being noticed. Larvae and adults feed
on foliage and flower buds.
Leaf beetle larvae feeding on foliage
of lance leaf coreopsis
Leaf beetle adults begin feeding on coreopsis
Beetles are gregarious feeders and can defoliate plants rapidly
Coreopsis rosea defoliated by leaf beetles
A predaceous stink bug feeding on a leaf beetle larva on coreopsis
Key Pests of Columbine
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Columbine leafminers
A. canadensis is less susceptible to leafminers
Pests of Cotoneaster
Eggs
Hawthorne lace bug
Key Pests of Crapemyrtle
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Crape myrtle aphid
Japanese beetle
Asian ambrosia beetle
Altica flea beetle
Crapemyrtle Pest Management Calendar
Pest
Winter
DecFeb
Spring
Summer Fall
Mar-May Jun-Aug Sep-Nov
Crapemyrtle
aphid
Ambrosia
beetle
S
S PS
SC P
Japanese
beetles
Altica flea
beetles
S
S
Japanese Beetle (Popillia japonica)
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Adults are nearly ½ inch long, broadly oval, thick bodied, with coppery
grown wing covers and a metallic green body. Mature larvae are nearly 1
inch long and white, with brown heads. They resemble several other scarab
beetle larvae, but may be identified by the shape of the raster (an area of
bare spots, hairs, and spines on the underside of the last abdominal
segment). There is one generation a year. Larvae overwinter in soil.
Adults of this imported scarab beetle feed on the flowers and leaves of
many plants. Preferred plants include rose, crapemyrtle, maples, sycamore,
birch, cottonwood, linden, mountain ash, and elms.
Look for adults on preferred hosts from early June through August. Weekly
application of residual or contact insecticides to host plants in June through
July will provide only partial adult control. Traps usually are
counterproductive and most often call in more beetles than they trap. Use
traps to time insecticide application for adults. Do not use traps for control.
Japanese beetle
Crapemyrtle Aphids
Asian ambrosia beetle
Adult flight peaks occur in late winter and early spring
Altica flea beetles
Often attack susceptible crape myrtles
In the Spring
Key Pests of Dogwood
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Dogwood borer
Dogwood twig borer
Dogwood clubgall midge
Cottony maple scale
Dogwood Borer (Synanthedon scitula)
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The adults are clearwing moths about 3/8 inch long. They have two
gold bands on a bluish-black abdomen. The larva grows to ½ inch
long and are white with a brown head and have two reddish-brown
spots on the back, near the head. There is one generation a year.
Larvae overwinter under bark. Adult emergence peaks around early
to mid-May, but occurs continually from April to October because
eggs are laid for several months.
Look for brown frass around wounds and bark cracks. Remove
loose bark with a knife. Larvae may be found in short tunnels under
bark near wounds.
An early April application of a long residual insecticide to the bark
should prevent infestation. An additional application may be
necessary in late May. Kousa dogwood appears resistant to this
borer.
Dogwood borer
Cottony Maple Scale (Pulvinaria
innumerabilis)
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Adult females are about 3/16 inch long. They are black, flat,
and oval. The 1/4-inch white cottony ovisac, or egg sac, is
deposited on bark. Crawlers appear in June and immatures in
summer on the underside of leaves. There is one generation a
year. Immatures overwinter on twigs. Preferred hosts include
maple, elm, hawthorn, dogwood, sycamore, poplar, and linden.
Look for white ovisacs on bark in early spring. During the
summer, look on underside of leaves for flat, yellow
immatures sucking sap from leaf veins where honeydew and
sooty mold are found on the host plant.
Apply dormant oils to bark to kill overwintering nymphs.
Horticultural oil or insecticidal soap can be applied to leaves
during the summer to control crawlers
Cottony Maple Scale (Pulvinaria
innumerabilis)
Key Pests of Gardenia
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Citrus whitefly
Armored scales (tea, greedy and oleander)
Cottony cushion scale
Whitefly larvae and an adult
Whiteflies
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Adult whiteflies range from 1/16 to 1/8 inch in length. Most species
resemble tiny white moths. Identification is easiest using the scale insectlike pupal stage.
Whiteflies have numerous hosts, including rhododendron and azalea, ash,
dogwood, sycamore, sweetgum, honey-and black locust, barberries,
redbud, roses, and herbaceous plants like hibiscus and verbena, among
others.
When honeydew, sooty mold, or leaf yellowing is observed, examine the
underside of leaves for feeding adult and immature stages of whiteflies.
Ants foraging on leaves may indicate the presence of whiteflies.
Rake up and destroy fallen leaves. If honeydew or damage are
objectionable, spray the underside of leaves with soap or oil to conserve
beneficials. Remove heavily infested leaves. Predators and parasites usually
keep these pests at low levels in the landscape. In the nursery application of
systemic insecticides or IGRs may be required.
Tea scale
Cottony cushion scale damage on
pittosporum
Vedalia lady beetle larva and adult
feeding on cottony cushion scale
Vedalia beetle larva
Cottony cushion scale female with eggs
Key Pests of Holly
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Holly leafminers
Florida wax scale
Southern red mite
Two lined spittlebug
Armored scales (tea, oleander, greedy,
euonymus, pit)
Holly Leafminer (Phytomyza ilicis)
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Adult flies are about 1/8 inch long and black. The larvae are 1/8 inch
long yellow maggots that tunnel through leaves, creating serpentine
mine. Eggs are usually deposited in the midrib or leaf margin and
early mining occurs there. There is one generation a year. Larvae
overwinter in mines. Hard, late frosts extend adult egg-laying
activity and increase the pest population.
Summer to fall mining occurs in the midrib. The obvious, linear,
yellowish-green mine in the leaf surface occurs the following spring.
Several mines per leaf cause premature leaf drop. Adult females of
this imported fly puncture tender new holly leaves to feed on plant
juices.
In heavy infestation, use systemics for larvae in March of late
summer. Contact insecticides may be used for adults in early May,
but this is the least desirable technique because beneficial parasites
may be killed
Two lined spittlebug
Twolined Spittlebug (Prosapia
bicincta)
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Adults are about 1/4 to ½ inch long, smoky brown to black in color,
broadly oval, convex, with prominent eyes. They have two bright orange
stripes across their wings. Adults sometimes are called froghoppers.
Nymphs are smaller, usually pale greenish-yellow, and covered by frothy
bubbles called spittle. Two generations occur per year.
The immature stages are found in turfgrass and adults may be found on
numerous woody ornamentals, especially hollies.
Look for active adults beginning in early summer. The second generation of
adults usually appears in August/September. If spittlebugs are coming from
surrounding turf, don't allow a heavy thatch layer to accumulate in the turf.
Where possible, avoid locating susceptible host plants (hollies) near
centipedegrass, a favored host for nymphal development.
Wax scale on holly
Wax Scales (Japanese, Florida, or
Indian wax scale) Ceroplastes spp.
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Adult females are about 1/4 inch long and reddish. They are covered
with a gummy, white wax that look like a dunce cap. Immatures
resemble cameos with the developing areas of white was not yet
completely covering the reddish body. There is one generation a year.
Adult females overwinter on bark.
Wax scales feed on many shrubs and trees, but Japanese holly, Chinese
holly, euonymus, boxwood, firethorn, spirea, barberry, and flowering
quince are preferred.
Large numbers of foraging bees, wasps, hornets, and ants on dense
shrubs may indicate wax scale. Look for honeydew and sooty mold.
Look on twigs and small branches for all wax scale stages. Crawlers
begin hatching in early summer in Georgia.
Beginning in May, examine female wax scales on leaves and branches
every one to two weeks and determine when eggs begin to hatch.
Remove heavily infested twigs or branches. Infested twigs and
branches must be sprayed thoroughly with horticultural oil, insecticidal
soap, or a contact or systemic insecticide after egg hatch and when
crawlers are present on the plant to achieve effective control.
EUONYMUS SCALE (Unaspis
euonymi)
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Covers of adult females are about 1/8 inch long, brownish
black, and are oyster shell shaped. Male covers are smaller,
thinner, and white. Crawlers are yellowish orange and are most
often found on new growth. Fertilized adult females
overwinter. There are four overlapping generations a year.
Light infestations on bark cause no obvious damage. In heavy
infestations, the white covers of males are easy to spot on the
leaves and the leaves develop yellow spots.
Always examine Euonymus japonica to discover infestations
before they cause damage. Carefully examine bark on a few
stems to detect light infestations. Examine plants for presence
of predators and parasites.
Time application of horticultural oil, insecticidal soaps, or
other contact insecticides for the presence of crawlers
Euonymus scale
Key Pests of Juniper
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Spruce spider mites
Bagworms
Juniper Scale
Spruce Spider Mite (Oligonychus
ununguis)
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Adults are about ½ mm long. They have eight legs and are yellowish-green when
young. When mature and fully fed, they are grayish-black with a tan area behind
the mouthparts. Immature forms are smaller and lighter in color. Eggs are oval to
circular and reddish brown. There are several generations a year. Eggs overwinter
on bark and needles.
This cosmopolitan pest prefers spruce, pine, hemlock, and arborvitae. Cedar, yew,
larch, cryptomeria, dawn redwood, fir, Douglas fir, and false cypress also may be
attacked.
At the first sign of stippling on needles, tap branches over white paper and count
the dark, slow-moving spider mites. Note the presence of white, fast-moving
phytoseiid predatory mites and the minute, black lady beetle mite predators.
Concentrate monitoring activities from March through June and September through
November.
Spraying is not recommended unless stippling damage exceeds ten percent of green
foliage; more than ten spider mites, on the average, are tapped from a tree's
branches; and beneficial mites and beetles are not found in all branch samples. Use
dormant oil sprays when overwintering eggs are abundant. In the growing season,
use summer oil or insecticidal soap sprays if predator populations are present.
Sampling for mites; pest and predator mites
Juniper Scale (Carulaspis juniperi)
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Mature female covers are circular, white, and about 1/16 inch
in diameter. Male covers are smaller, elongate, oval, and white.
Shed skins incorporated into the cover are yellow. There is one
generation a year. Adult females overwinter on needles.
This imported armored scale insect prefers juniper, but has
also been collected from Leyland cypress and cedar. Yellow
crawlers are present in late spring.
Dormant oil spray will reduce the number of adults that
successfully overwinter, but usually does not provide adequate
control. Use horticultural oil or insecticidal soap to control
crawlers in late spring. Systemic insecticides may be used to
reduce heavy populations of scales in late summer and fall.
Key Pests of Lantana
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Whitefly
Lantana lace bug
Whitefly and lantana lace bug
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11 lantana cultivars
evaluated for resistance to
greenhouse and silverleaf
whitefly and lantana lace
bug
Larger-leaved cultivars very
susceptible and may serve
as indicator plants
Key Pests of Maple
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Cottony Maple Scale
Green Striped Mapleworm
Tip Borers
Leafhoppers
Flatheaded apple tree borer
Japanese beetle
Asian ambrosia beetle
Aphids
Cottony Maple Scale (Pulvinaria
innumerabilis)
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Adult females are about 3/16 inch long. They are black, flat,
and oval. The 1/4-inch white cottony ovisac, or egg sac, is
deposited on bark. Crawlers appear in June and immatures in
summer on the underside of leaves. There is one generation a
year. Immatures overwinter on twigs. Preferred hosts include
maple, elm, hawthorn, dogwood, sycamore, poplar, and linden.
Look for white ovisacs on bark in early spring. During the
summer, look on underside of leaves for flat, yellow
immatures sucking sap from leaf veins where honeydew and
sooty mold are found on the host plant.
Apply dormant oils to bark to kill overwintering nymphs.
Horticultural oil or insecticidal soap can be applied to leaves
during the summer to control crawlers
Cottony Maple Scale (Pulvinaria
innumerabilis)
Aphids
Aphids often attack
new growth on plants
early in the year
Wooly aphids on Maple
Flatheaded Appletree Borer
(Crysobothris femorata)
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Adults may reach ½ inch in length. They are oval, flattened beetles, metallic
greenish bronze above and brassy below. The wing covers have wavy, light-colored
indentations. The white larvae, commonly called flatheaded borers, are expanded
just behind the true head, which is black. There is one generation a year. Larvae
overwinter in galleries inside the host plant.
Preferred hosts include sycamore, red maple, silver maple, willow, oak, tuliptree
poplar, elm, beech, hickory, apple, pear, dogwood, and black walnut.
Larvae bore fairly large, irregular cavities in phloem tissue of the main trunk and
larger branches. Young trees and trees under stress are particularly attractive to this
pest. Larvae are usually found boring into the base of trees. Small trees often are
killed.
Adults run over bark and are quick to fly. They are most active on exposed, sunny
bark of weakened trees from early March through May and early September
through October.
Maintain vigor through use of good cultural practices. If numerous adult beetles are
noted on bark, spray the trunk and major branches with an approved residual
insecticide
Maple Bladdergall Mite and Maple
Spindlegall Mite (Vasates quadripedes
and V. aceriscrumena)
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Adults of these two eriophyid mites are not visible
without a hand lens. They live in circular and spindleshaped galls. They are white to clear in color, 0.15
mm long, cigar-shaped with only four anterior legs.
There are several generations a year. Adult forms
overwinter in bark cracks.
While control measures usually are not necessary in
the landscape, pyrethroid application when leaves
first flush may prevent new galls in the nursery.
Where feasible, affected leaves can be removed on
plants not scheduled for sale.
Maple bladder gall
Key Pests of Oaks
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Orange striped oakworm
Lecanium scale
Insect galls
Obscure scale on Oak
This scale has been attacked by fungus
Parasite emergence holes
are visible on these scale covers
Obscure Scale (Melanaspis obscura)
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Fully enlarged adult female covers may reach 1/8 inch in diameter. They
are circular, brown to gray, slightly convex, with central shed skins that are
black when rubbed. Male covers are smaller and broadly oval. This species
develops in overlapping aggregations. There is one generation a year.
Immatures overwinter and crawlers appear in July.
Look on three to four-year-old branches for overlapping gray scale covers.
Scrape off covers to determine viability of a population because covers of
dead scales may remain attached. In midsummer, live adult female scales
are light purple. Scout in mid-July to determine amount of crawler activity.
Look under covers in the dormant season for the small, yellow immatures
to see if dormant sprays are needed. Look for holes in covers to estimate
level of parasitism.
Concentrate dormant oil sprays on three- to four-year-old growth to reduce
overwintering populations. Spray summer oil in late July to kill newly
settled crawlers. Several parasite species are active when the scale crawlers
appear in July. Avoid synthetic insecticide sprays at this time.
Orange Striped Oakworm
Orangestriped Oakworm (Anisota
senatoria)
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Adult moths are about 1-1/4 inches long with wings closed. They are reddish
brown, translucent, with a submarginal dark stripe and a white spot on each
forewing. Mature larvae are about 1-1/2 inch long. They are black with eight
orange-to-yellow stripes and two black spines behind the head. Adults first appear
in early summer. Pupae overwinter in soil.
This native notodontid moth caterpillar prefers to feed on oaks, but it also attacks
hickory and birch.
The caterpillars are gregarious and early instars feed by skeletonizing the leaf
surface. Older caterpillars are defoliators and may consume all but the leaf midrib.
Defoliation usually occurs one branch at a time when populations are small.
Look for signs of localized skeletonization turning to defoliation on host tree
branches. Where this species is a serious problem, a black-light trap can be used to
determine the first adult appearance and the relative size of each generation.
Manually destroy aggregations of young larvae when they are detected on small
trees. Application of Bacillus thuringiensis or horticultural oil will control young
larvae. Contact insecticides often are required to control large caterpillars.
Oak Lecanium (Parthenolecanium
quercifex)
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Fully developed adult females are about 1/4
inch long. They are oval to almost circular,
highly convex and light to dark brown.
Crawlers are pale yellow. There is one
generation a year. Immatures overwinter on
twigs.
Key Pests of
Oenothera

Altica flea beetles
Other insect pests



Oleander aphid on Asclepias
Eastern tent caterpillar
Fall webworm
Oleander aphid


24 Asclepias taxa
evaluated
Gradients in
susceptibility suggest
options in high density
aphid areas
Oleander aphid


A. tuberosa and A.
physocarpa maintained
better appearance
Numerous natural
enemies colonize
milkweed plants with
aphids
Eastern Tent Caterpillar (Malacosoma
american)




Adult moths are about 1 inch long. They are light brown with two
white diagonal stripes across each forewing. Mature larvae may
reach a length of 2 inches or more. This is the only common
caterpillar with a white stripe down the back. There is one
generation a year. Pupae overwinter in cocoons in debris on the
ground.
Silken webs in tree forks at budbreak are indicative of this pest. In
peak population years, preferred hosts can be defoliated.
Look for the black 3/4 inch-long egg masses on preferred hosts in
the dormant season. Look for silken webs in the branch forks of
preferred hosts in early March.
Prune out the egg masses during the dormant season. Mechanically
destroy the web contents when first discovered. Time insecticide
application for the presence of young larvae.
Fall Webworm (Hyphantria cunea)




Adult moths are about 3/4 inch long with wings folded. Wings are all white
or white with black spots. Bases of front legs are orange-yellow. Mature
larvae are about 1 inch long and may occur in two color forms: those with
black heads are yellowish white and those with red heads are brown. Both
forms have paired black tubercles running down the back. They are
covered with long, silky gray hairs. There are four generations a year.
Pupae overwinter in flimsy cocoons in protected places.
Preferred hosts include mulberry, walnut, hickory, elm, sweet gum, poplar,
willow, oak, linden, ash, and apple and other fruit trees.
The caterpillars produce a "web" of fine silk over terminals. They feed
inside the silken web, which they enlarge to take in more foliage as they
grow.
In early spring, examine the south side of tree crowns for the first signs of
webbing over terminals. Insecticides must penetrate the" nests" to provide
good control
Key Beneficial Insects
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Lady beetles
Ground beetles
Tiger beetles
Rove beetles
Syrphid flies
Long-legged flies
Robber flies
Spined soldier bugs
Predaceous damsel bugs
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Minute pirate bugs
Predaceous plant bugs
Assassin bugs
Big-eyed bugs
Green lacewings
Brown lacewings
Parasitic wasps
Parasitic flies
Predatory beetles

Ground Beetles (Carabidae) are predaceous as adults and as larvae. There
are some seed feeding species. They are active on the ground primarily at
night. Adult beetles vary in size from 1/4 to 1 inch or longer. Many species
are metallic, while others are plain brown or black.

Lady Beetles (Coccinellidae) are among our most important beneficials.
Adults and larvae feed on aphids, scale insects, mites, mealybugs, other
soft-bodied insects and their eggs. Lady beetle adults are oval-shaped. Most
are orange or reddish with black markings.
Lady beetle larvae are elongate, covered with spines, and dorso-ventrally
flattened. Often they are brightly colored with spots. Some larvae are
covered with white waxy secretion like mealybugs. Adults and larvae are
voracious feeders on aphids, a single individual consuming hundreds of
aphids during its lifetime.



Rove beetles (Staphylinidae) have shortened elytra (wing covers) that
leave the segments of the abdomen visible giving these beetles their
characteristic appearance. Most species are slender and elongate from 1/161/2 inch long. Typically they are reddish-brown to black. Many species are
predaceous, some feed on decaying organic matter helping to recycle
needed nutrients in the landscape.


Tiger Beetles (Cicindellidae) are very active, often metallic beetles 1/23/4 inch long. They are difficult to collect because of the speed with which
they run or fly. Larvae live in burrows in the soil and ambush prey as it
goes by.
Earwigs
Earwigs (Dermaptera)

Many species are predaceous. Earwigs vary in
size, some of the larger species are 3/4-1 inch
long. They are usually brown and may have
stripes.
Predators in the “True Bug” group

True Bugs (Hemiptera) is a group that contains several generalist predator species.
These insects all have piercing-sucking mouthparts which they use to impale their prey
and extract fluid. The beak is usually carried beneath the body, but can be pointed
forward or downward while feeding. The usual prey for these insects are other softbodied insects of small to intermediate size. Representatives of these predators include :

Assassin Bugs (Reduviidae) generally appear oval or elongate and are often black and
orange-red or brown. They are larger than most of the other predaceous bugs, especially
the giant wheel bug. Assassin bugs have a head that has a particularly long and narrow
appearance. They feed on most other insects and will inflict a painful bite if handle
Big-Eyed Bugs (Lygaeidae) are stout bodied insects, about 1/8 inch long with prominent
eyes that give the insect its name. These insects are slightly larger than chinch bugs.
They may have similar coloration, but are always broader across the head than the area
just behind (shoulders). Chinch bugs, on the other hand, have a narrow head, never
broader than the area directly behind. Often big-eyed bugs can be found with populations
of chinch bugs and it is important to be able to distinguish predator from pest. Big-eyed
bugs also feed on caterpillars and insect eggs.



Minute Pirate Bugs (Anthocoridae) are 1/8 - 1/4 inch long. These insects are black and
white as adults and have colorful yellow-orange-brown nymphs depending upon instar.
Gardeners notice the painful bite that this small insect produces. It is an effective
predator of thrips and the eggs of many insect and mite species.
Predaceous Damsel Bugs (Nabidae) are 1/8 - 3/8 inch long and may be cream colored
to dark brown to black depending on the species. The most common species are slender,
elongate insects that are most active in mid summer. They feed on eggs and immature
stages of many pest insects.
Predaceous Plant Bugs (Miridae) are less well known than other predaceous true bugs,
but have been shown to be active predators of thrips, lace bugs, aphids, moth eggs and
other insects of importance in the landscape.
Predatory flies

Long-Legged Flies (Dolichopodidae) are small, about 1/4 inch with very
long legs in relation to the body and usually metallic blue or green in color.
Adults and larvae are predaceous and are often found near woodland
streams or other wet areas. Predaceous Midges (Cecidomyiidae) Most
members of this group are gall makers on plants but there are some
predaceous members of the family that feed on aphids. These larvae look
much like syrphid larvae, but smaller.

Robber Flies (Asilidae) are 3/4 - 1 1/4 inch long and vary in appearance.
Some are quite stout while others are long and slender. The face is usually
bearded and the head is hollowed out between the eyes. Adults are
predaceous on many kinds of insects and usually capture their prey in the
air. Larvae are soil-dwelling and predaceous on such things as white grubs.

Syrphid Flies (Syrphidae) are sometimes called flower flies because they
are commonly found on flowers or hover flies for their behavior in flight.
Most of these flies are yellow with brown or black bands on the abdomen.
Some resemble wasps, many mimic bees.

Syrphid larvae are maggot-like and predaceous on aphids and other softbodied insects. They have no legs or visible head capsule and are
translucent.
Spiders and mites


Mites are more closely related to spiders than they are to
insects. Mites do not have antennae like insects do, or
segmented bodies or wings. They are usually very small and
often go unnoticed. Most mites have an egg stage, a six-legged
larval stage, and two eight-legged stages before becoming an
adult. Phytoseiid mites are the major group of natural enemies
that attack certain kinds of pest spider mites. It is especially
important to conserve predatory mites in the landscape to
prevent pest mite outbreaks. Other insect pests are also eaten
by predatory mites including whiteflies, thrips, and certain
insect eggs.
Most predaceous mites are somewhat pear-shaped and shiny,
with noticeably long legs. They may be bright red, yellow, or
green depending on what they've been eating and appear "seethrough". Predaceous mite eggs are usually oblong instead of
spherical like the eggs of pest mite species. Predaceous mites
are also much more active and mobile than pest mite species.

Spiders are all predators, but have many different
lifestyles. Some make webs and wait for prey to come
to them while others are active hunters. Spiders are
important predators in the landscape and are very
common in trees, shrubs, grass, and herbaceous plant
beds. Most spiders are general predators, feeding on a
wide variety of prey. Their are a number of spider
species that may be found in the landscape. All have
two body parts, an abdomen and a cephalothorax
(combined head and thorax), and eight legs. Spiders
tend to avoid people and most are harmless to
humans. Spider complexes are believed to be
important in reducing several kinds of nursery pests.
Thrips

Thrips (Order Thysanoptera) are very small,
narrow insects with fringes on the edges of their
wings. Many species are recognized for their plant
feeding (pest) habits, but there are many predaceous
members of this insect order. These important
predators of mites and small, soft-bodied insects are
commonly black, yellow or brown as adults and clear
or translucent white-yellow as immatures, although
some are a distinctive reddish-orange in color.
Lacewings
Lacewings (Chrysopidae,
Hemerobiidae)

Both green lacewings and brown lacewings are
predators, green lacewings are more common. They
are often found on weeds, shrubs, and other cultivated
plants. Adult green lacewings are about 3/4 inch,
brown lacewings are smaller. Adult and larval brown
lacewings and larval green lacewings feed on softbodied insects, especially aphids, and mites. Adult
green lacewings may be pollen-feeders or they may
be predaceous. Most are greenish in color with
copper eyes and the network of veins in the wings
that gives them their name.
Praying mantids


Praying Mantids (Mantidae) are comparatively
large insects. Some may be as long as 3 in. Our native
species are much smaller, however. Usually they are
green, gray, or brown. Their raptorial front legs are
covered with stout spines that help them grasp their
prey.
Mantid egg capsules contain 200 or more eggs neatly
arranged in rows. They are deposited on twigs and
stems and then the frothy mass hardens. It is very
unlikely that praying mantids can suppress key pests
in the landscape to the extent necessary
Parasitic wasps and flies

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Parasites are defined as organisms that live in or on the body of their host during
some part of the parasite's life cycle. Parasitoids are a type of parasite that may
consume part or all of its host's tissues resulting in the death of the host. The most
abundant parasitic insects are flies or wasps. Parasitic insects usually require only
one host to complete their development, in contrast to predators which require
several. Parasitic insects may be responsible for controlling several pests, however,
when they oviposit, or lay eggs, on a number of hosts.
Parasitic Wasps are a large group of beneficial insects and are extremely important
in biological control. Many wasp families contain representatives of the parasitic
life style. Most of these wasps are very small <1/8 inch and are , therefore, rarely
seen. A large number in fact attack the egg stage, completing their entire life cycle
inside minute insect eggs.
Parasitic wasps lay their eggs in or on the host and the immature stage of the wasp
feeds on the hosts tissues. The parasitic wasp may emerge from its host to pupate,
or it may pupate within the body of its host. Wasp larvae that develop inside the
host are called endoparasitic. They leave evidence of parasitism when they chew a
small hole in their host's body to emerge. That small circular hole indicates that
parasitism is occurring in the pest population. Insects that you may find parasitized
this way include scales, aphids, whiteflies, lace bug eggs, leafminers and
caterpillars. Other parasitic larvae live on the outside of the host's body and are
called ectoparasites. Both endo and ectoparasites may spin numerous white cocoons
for pupation, another obvious indication of parasitism.
Parasitic Flies are abundantly represented by the family Tachinidae, with about
1,300 North American species. They vary tremendously in appearance. Many just
resemble a common husefly, while others look like bees or wasps. These flies
deposit an egg or in some cases, a live larva, on or near the body of their host. The
tachinid larva burrows into its host and consumes the internal tissues. Numerous
kinds of insect pests are attacked by tachinids.
Pests to be on the lookout for
January- December


Insects that are active or that can be scouted
for (SC), pruned out (P), sprayed (S), or
treated with dormant oil (D) are listed in the
following slides during the months where these
activities would be appropriate.
See individual plant based calendars in
previous slides for more details.
January

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
Southern red mite-S
Armored scales – DO
Bagworms- remove bags where feasible
Asian ambrosia beetles- may be active this
early some years in some locations
Flea beetles may be active in some locations
February
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Southern red mite-S
Cottony maple scale-S
Armored scales-S
Bagworms-P
Spruce spider mites-S
Azalea lace bug- SC (scout for eggs)
Asian ambrosia beetle-S
Leaf beetles on coreopsis and primrose-SC
March

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Azalea lace bug-S
Strawberry rootworm
Azalea stem borer-S
Boxwood Leafminer- sc
Boxwood psyllid-S
Armored scales-S
Asian ambrosia beetle-S
Cottony maple scale-S
Citrus whitefly-SC
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Holly leafminer-S
Bagworms- SC
Spruce spider mites-S
Aphids-S
Flat headed apple tree
borer-S
Dogwood twig borer-S
Insect galls on oaks and
maple-S
April

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Azalea lace bug-S
Azalea leaf miner-S
Strawberry rootworm
Azalea bark scale-S
Azalea stem borer-S
Boxwood leaf miner-S
Leaf beetles on coreopsis,
primrose and crapemyrtle-S
Spruce spider mite-S
Bagworms-S
Cottony maple scale-S
Borers on maple-S
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Boxwood psyllid--S
Tea scale and other armored
scales-S
Asian ambrosia beetle
Dogwood borer-S
Dogwood twig borer-S
Dogwood clubgall midge-P
Citrus whitefly-S
Armored scale on gardenia
Holly leafminer-S
Lecanium scale-S
Aphids-S
Insect galls on oaks and maple-S
May
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Azalea leaf miner-S
Azalea bark scale-S
Azalea stem borer-S
Boxwood leafminer-S
Indian wax scale-S
Boxwood psyllid-S
Scales on boxwood, gardenia,
holly, camelia-S
Crape myrtle aphid-S
Japanese beetle first appearance
Flea beetles on crape myrtle and
primrose-S

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Dogwood borer-S
Dogwood clubgall midge- prune
Dogwood twig borer-S
Citrus whitefly
Wax scale on holly and others-S
Caterpillars-S
Aphids-S
Borers-S
Lecanium scales on oak-S
Insect galls on oak and maple-S/P
June

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Azalea leafminer-S
Azalea stem borer-P
Two spotted spider mite-S
Indian wax scale-S
Armored scales-S
Crape myrtle aphid-S
Japanese beetle-S
Dogwood borer-S
Dogwood clubgall midge-P
Cottony maple scale-S
Citrus whitefly-S

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Florida wax scale-S
Two lined spittlebugs-S
Juniper scale-S
Bagworms-S
Aphids-S
Lecanium scale-S
Oak galls-P
July




Two spotted spider
mite-S
Crape myrtle aphid-S
Dogwood borer-S
Dogwood clubgall
midge-P

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

Citrus whitefly-S
Bagworms-S
Maple and oak galls-P
Cottony maple scale-S
August

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


Azalea caterpillar-S
Two spotted spider
mite-S
Crape myrtle aphid-S
Citrus whitefly-S
Bagworms-S


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
Insect galls on oaks-P
Two lined spittlebugs-S
Orange striped
oakworm-S
Green striped
mapleworm-S
September

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
Green striped mapleworm-S
Orange striped oakworm-S
Azalea caterpillar-S
Crape myrtle aphid-S
Citrus whitefly-S
Two lined spittlebugs-S
Bagworms-S
October

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Southern red mite-S
Crape myrtle aphid-S
Asian ambrosia beetle- P
Spruce spider mite-S
Orange striped oakworm-S
November

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
Southern red mite (azalea, camelia, holly)-S
Armored scales- DO (boxwood, camelia, holly,
gardenia, etc.)
Spruce spider mite-S
Bagworms- P
Maple borers- P
Lecanium scale -DO
December

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
Southern red mite (azalea, camelia, holly)-S
Armored scales- DO (boxwood, camelia, holly,
gardenia, etc.)
Spruce spider mite-S
Bagworms- P
Maple borers- P
Lecanium scale -DO
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