basic entomology master gardener training€¦ · –integrated pest management . insect...
TRANSCRIPT
Basic Entomology
Master Gardener Training
Dan Nortman
Extension Agent, ANR-Horticulture
York/ Poquoson
What is an insect?
Exoskeleton
• Regulates water
• Provides structure
• Waxy coating acts in a protective manner
• Represents evolution
Six Legs
Usually specialized for the
insect’s lifestyle
Wings
Size
.17 mm
Antennae
How insects taste the world around them and communicate with each other
Taxonomy
• Kingdom: Animalia
• Phylum: Arthropoda
• Class: Insecta
• Order: ~32 (Coleoptera)
• Family: >700
(Curculionidae)
• Genus
• Species
Specific epithet:
Conotrachelus nenuphar
How many? 1-10million
Plum Curculio
Arthropods
• Hard shell
(exoskeleton)
• Body
segmentation
• Jointed legs
Non-insect Arthropods
• Crustacea
• Arachnida
• Symphyla
Non-insect Arthropods
• Chilopoda
• Diplopoda
Non-insect Arthropods
• Crustaceans- Isopods- 5pr. Legs
• Arachnids- spiders, ets.- 4 pr. Legs
• Symphyla- Small, many legs, translucent
• Chilopoda- “one-leg” (one leg per
segment)- flat in x-section
• Diplopoda- “two-leg” (double legs per
segment)- round in x-section
Arachnids- Spiders
• Predatory
• Venemous- rarely
enough to kill or do
serious harm
• Two body segments
• Beneficial generalist
predators
– Inefficient
Arachnids- Opiliones
• Harvestmen, daddy
longlegs
• Detritivores
• No venom
• One body segment
(fused abdomen and
cephalothorax)
Arachnids- Ticks
• Two body segments,
though hard to tell
• Very common human
and animal pests
• Lyme disease
– Only Black legged
(deer) tick
Dog Tick
Deer Tick
Lone Star Tick
Arachnids- Mites
• Many niches
• Some serious plant
pests
• Eight legs, one body
segment
• European red mite
• Two spotted spider
mite
Spruce mite on arborvitae
Spruce mite on Fraser fir
Spruce spider mite
• Overwinter as eggs
• Egg hatch begins at 20 C
• Optimum 26 C, 50-60% RH
• 10 generations annually
• High mortality at higher temperatures
Checking for Spider Mites
• Monitor
– Hot sites
• Check for mites
– Tap test
• Treat
– At peak of activity
• Avoid
– Planting in hot sites
Southern red mite
Two-spotted spider mite
Oak mite damage
Chilopoda
• Centipedes
• Predators
• No dangerous
species in VA
• Some tropical species
are dangerous
• Common: house
centipede
Diplopoda
• Millipedes- 2 legs per
segment
• Feed on decaying
plant material
• Not really a pest
• Overwintering
irritation
Exoskeleton
• Regulates water
• Provides structure
• Waxy coating acts in a protective manner
• Represents evolution
Six Legs
Usually specialized for the
insect’s lifestyle
Wings
Antennae
How insects taste the world around them and communicate with each other
Life Cycle Three ways
No metamorphosis
Incomplete/ Gradual
metamorphosis
Complete
metamorphosis
Why are insects important?
• Biodiversity
• Indicators of pollution
• Medical/ Human health
• Urban pests
• Animal health and happiness
• Crop production
– Pollination
– Integrated Pest Management
Insect identification
• Why is it important?
Thrips: General Pests: • Thrips are common pests of
beans and many other crops
including greenhouses.
• yellow spotting
• feed in buds
• distorted pods and fruit
• insecticidal soap, etc.
• common in dry years
• will bite
Thysanoptera
Hemiptera and Homoptera Mouthparts
“Homoptera”: Aphids
• Piercing mouthparts
• Honeydew
• Reduce vigor
• Many different
species and hosts
• Tended by ants
Aphids
note “tail pipes” life stages
distortion of birch leaf
Aphids
• Monitor for distorted
foliage
• Monitor for
honeydew, sooty
mold
• Monitor for natural
enemies
• Apply insecticidal
soaps
• Apply synthetic
insecticides
Homoptera: Scale insects Sedentary, Piercing mouthparts, hatchlings are the
only mobile stage (“crawlers”)
• Armored scales
– Small (1/8th
inch)
– Shield
– Crawlers
– Dormant oil
• Soft Scales
– Larger (1/4 inch)
– Hemispherical
– Crawlers
– Dormant oil
Scale Life Stages
Soft scale: Cottony maple scale
Cottony maple scale
Soft scale: Wax scale
adult scales infested boxwood
Homoptera, Soft scale:
Oak lecanium scale
scale with crawlers
infested branch
parasitic wasp
Homoptera: Armored scales
gloomy scale obscure scale
tea scale
parasitic
wasp
Euonymus
scale
Armored Scales – Oystershell Scale Lepidosaphes ulmi
Armored Scales – San Jose Quadraspidiotus perniciosus
Scale control, generally
• Monitor for sooty mold
• Monitor for natural enemies
• Apply horticultural oils in winter
• Avoid pesticides when predators are active
Scale Control
• Euonymous scale- May 10-20 July 5-15
• Lecanium scale- June 15-20
• Oak Kermes- June 10-15
• Oystershell Scale- May 5-20, July 20-25
• White Peach Scale- May 1-10; July 5-15;
and September 1-10
Hemiptera: Piercing
mouthparts,
hemielytra type wings
• Examples: Stink Bugs and Leaffooted bugs
• General Pests
• Common late summer feeders on fruits and pods
• white halos
• reduce weeds
Pantatomidae: Stink bug
Harlequin bug
http://insects.tamu.edu/images/insects/color/harleq2.jpg
Hemiptera:
Harlequin bug • Harlequin bugs are
common on kale,
mustard, and other
crucifers (cole crops)
including weeds.
• Type of stink bug
• yellow spots
• OW as adults
• clean plow in fall, remove
weeds.
Harlequin bug, adult
Hemiptera:
Squash bug • Squash bug is common in
spring and late summer
• all cucurbits
• row covers in spring
• Proper fertilization
• Removal and destruction
of crop debris after
harvest
• egg masses can be hand-
picked
• trap with boards, squash
bugs in AM
http://www.uidaho.edu/so-
id/entomology/Home_&_Garden/squash%20
bug.jpg
Squash bug, Hemiptera, Coreidae
Hemiptera: Azalea lace bug
life stages
damage to azalea
Azalea Lace Bug
• Monitor
– Overwintering population
– Adult emergence
• Selective spraying (sunny areas)
• Follow-up monitoring
Dermaptera
• Earwigs
• Very short front wings, with complex folding of hind wings
• Pincers
• Not a serious pest, but will thrive in groundcover
• Can damage mature fruits
• Trapping them in upturned flower pot with newspaper
Coleoptera
• Beetles
• Front wings hard or
leathery- elytra
• Larva are grublike,
generally
• About 25% of all life
• 350,000 described, 3-
8 million estimated
Coleoptera: Beetles. Chewing mouthparts
Coleoptera
• Scarabaeidae
• Buprestidae
• Cerambycidae
• Curculionidae
• Coccinellidae
• Meloidae
• Chrysomelidae
Scarabaeidae
• Scarab beetles
• Lamellate antennae
• Leaf feeders, some decomposers
• Common landscape and garden pests: – Japanese beetle
– Rose chafer
– Lawn grubs
– June beetles
Japanese beetle
• Very wide host range
• Foliar devastation-
Rosaceae
• Lawn trouble
• Lawn insecticides-
targeting grubs
• Milky spore- works
selectively
• Exclusion- Hand
pollination may be
required
• Shake into a soapy
bucket
Japanese beetles
adults feeding on leaf
Japanese Beetle
Buprestidae
• Flat headed borers
• Flat in profile
• Often very metallic
and pretty
• Most bore into dead,
dying trees
• Some attack healthy
trees
– Apple tree borer
– Emerald ash borer
Emerald Ash Borer (EAB)
In the wake of
Chestnut blight
& Hemlock
Wooly Adelgid
is EAB
Virginia’s next
tree/forest
disaster?
• Killed more than 40 million ash trees in southeastern
Michigan alone, with tens of millions more lost in OH, IL, IN, PA,
WV, MO, WI and VA.
• Cost municipalities, property owners, nursery operators and forest
products industries tens of millions of dollars.
Emerald Ash Borer: What to Look for
D-shaped emergence holes
Epicormic branching
Galleries Branch dieback
Cerambycidae
• Long horned beetles – Have very long
antennae
• Also wood borers
• Round in x-section
• Many minor pests that can become serious – Oak borer
– Locust borer
– Twig girdler
Cerambycidae
Roundheaded
Borers
Adults are called
longhorned beetles,
larvae are called
roundheaded borers
Twig Girdler
• Chews a ring on a twig to feed and lay an egg
• Twig dies, larvae develops in dead part
• Twig falls off of tree
• Many hosts – Pecan, hickory, oak
• Collect and burn fallen twigs
Borers • Look
– Early color change
– Dead branches
– Loose bark
– Sawdust
• Remove – Infested trees
– debark
• Treat – Neighboring trees of same species
• Secondary pests – Attracted to dead and dying trees
Curculionidae
• Two groups
– Weevils
– Bark beetles
• Weevils have snout,
bark beetles don’t
• Weevils feed on plant
material
• Bark beetles are
pests in wood
Weevils
• Wide variety of hosts
• Some common pests – Boll weevil
– Plum curculio
• Common in stored grains
• Botanical insecticides
• Not usually a problem for the home gardener
Bark Beetles
• Small, brownish
beetles
• Some eat wood
• Others eat fungus
that they “farm”
• Systemic
insecticides are
best
Damage comparison
Bark Beetle Buprestid
Coccinellidae
• Ladybird beetles
• Most are predator
– Extremely valuable
– Aphids, scales,
whiteflies, etc.
• One pest- Mexican
bean beetle
Mexican Bean Beetle
• Can be devastating in
large numbers
• Attacks most legumes
• Promoting biocontrol
is the best option, but
several insecticides
are available
• Planting early can
also help
Meloidae
• Blister beetles
• Spanish Fly
• Leathery elytra
• “Fleshy” bodies
• Occasional pests
• Botanical insecticides
are effective, most
general use
insecticides
Colorado Potato Beetle
• Orange and black
stripes on elytra
• Very, very destructive
• Prone to resistance
• The bane and funding
source of many, many
entomologists
• Handpick
• Bt, Neem
Neuroptera
• Lacewings
• “Little gator” larvae
• Adults feed on nectar
Lepidoptera: What is a
Caterpillar?
2-5
Eastern tent caterpillar
larva
eggs
tent
Eastern tent caterpillar: pest of wild
cherry and some fruit trees • Trees will put out leaves again
• Prune egg masses Nov.-Mar.
• Remove small tents manually
• Apply insecticides to tents
• Migrating last instar larvae cannot be controlled
• Recreational caterpillar burning: DO NOT torch tents
Gypsy moth
mature larva
laying eggs
defoliated forest
Gypsy moth -
treatments
pheromone traps
trapping with burlap bands
Fall Webworm
• Highly
Polyphagous
• Loves Pecan
• Damage
unsightly, but
usually negligible
larva
Lepidoptera: Bagworms
Bagworm
• Monitor degree of infestation
• Handpick overwintering bags
• Monitor egg hatch beginning in May
• Apply microbial insecticides
• Apply synthetic insecticides
http://www.hort.uconn.edu/ipm/veg/pics/icw2.jpg
Imported cabbageworm:
Lepidoptera
Squash Vine borer
• Squash vine borer
found on most
cucurbits
• Lepidoptera
• 2 generations/year
• row covers
• cut out worms
• dirt every 4-6 feet
• insecticides ASAP
after seeing damage
http://www.oznet.ksu.edu/
dp_hfrr/HortImage/Squash
%20Vine%20Borer%20La
rva.gif
Tomato
Hornworm
• Tomato hornworms are
late summer defoliators
• hand-pick, keep
parasitized worms
• Tobacco hornworm,
Manduca sexta
• Tomato hornworm,
Manduca
quinquemaculata
Tomato hornworm parasites
Photo form Stuart Sutphin
Sesiidae
• Clearwing moths
• Borers
• Common tree fruit
borers
– Peachtree borer
– Plum borer
– Dogwood borer
Sesiidae
• Look
– Damage esp. at graft
sites
– Trap for moths if you
suspect a problem
• Treat
– Flying moths that have
not laid eggs (timing)
– Treat at sites when
moths reach
thresholds
Hymenoptera
• Bees, wasps, sawflies
• Important beneficials
– Pollinators
– Parasitoid wasps
• Major pest: sawflies
Parasitoid wasps
• Braconidae
• Ichneumonidae
• Trichogrammatidae
Sawflies
• Pests of evergreens
and other plants
• Caterpillar like larvae
• 6+ pairs of prolegs
Diptera
• Flies
• Two wings
• Few common garden pests
– Seed corn maggot
– Fruit flies
• Several important beneficial
– Syrphid fly
– Cecidomyiids
– Tachinids
Syrphid Fly
• Larvae are excellent
predators
• Adults are nectar
feeders
– Bee mimics
Cecidomyiid larvae
• Small larvae, excellent predators
• Predatory Midge
Tachinids
Dan Nortman
Virginia Cooperative Extension
Extension, Agriculture and Natural
Resources, Horticulture
100 County Drive, Yorktown, VA
757-898-4940