Contents: By Damage and Image
In progress
Contents: Alphabetical

alder flea beetle
aphid management
apple and thorn skeletonizer
apple ermine moth
ash whitefly
azalea bark scale
azalea lace bug
azalea sawfly
Bagrada bug
bark lice
Barypeithes root weevil
Beneficial nematodes
biocontrol of root weevils
birch aphid
black bean aphid
black cherry aphids
black stem borer
bluegum psyllid
Boisduval scale
branch and twig borer
brown marmorated stink bug

bronze birch borer
boxwood leafminer
boxwood psyllid
bulb flies
cabbage whitefly
carnation tortrix
carpet beetle (images)
Calligraph californica

Ceanothus stem gall moth
cereal leaf beetle
cherry ermine moth
chilli thrips
cinnabar moth
clay colored weevil
cottony camellia scale

crane flies
cypress tip moth

dogwood sawfly
Douglas fir sawfly
Douglas fir twig weevil
elm leafminer
European pine sawfly new
European pine shoot moth
European wool carder bee
emerald ash borer
Fall webworm
fir coneworm new
flatheaded cedar borer
ground beetle gallery
Hemerocallis gall midge new
hollyhock weevil
honeylocust plant bug
honeylocust pod gall midge
Heliothis phloxiphaga
holly bud moth
huckleberry root aphids
ground mealybug
Japanese beetle
lady beetle gallery
leaf weevil
light brown apple moth
Linden aphid new
lupine aphid new
Macrosiphum rhamni new
maple aphids
maple tip moth
maple midge
March flies
mountain ash sawfly
Myzocallis sp. on red oak new
Narcissus bulb fly
natural enemies gallery
oak ambrosia beetle
oak slug
oak twig gall wasp
obscure root weevil
Pacific flatheaded borer
peach tree borer
peach twig borer
pear blight beetle
pear psylla
pear leaf-curling midge
pear sawfly
pine needle scale
pine and cone spittlebug
poplar and willow borer
Psyllopsis fraxinicola
rose curculio weevil
rose midge
rove beetle gallery
rose stem girdler
sequoia pitch moth
soldier beetle gallery
snapdragon plume moth new
snakefly gallery
speckled green fruitworm
meadow spittlebug
spotted asparagus beetle
spruce twig aphid
tent caterpillars
viburnum leaf beetle
violet gall midge
western poplar clearwing
western spotted cucumber beetle
white pine weevil
woolly alder aphid new
woolly ash aphid
woolly beech aphid

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Fall Webworm

One can find the fall webworm, Hyphantria cunea (Drury), in late summer in the Pacific Northwest. They weave a web around themselves and the tree branch on which they dine. They rarely cause significant damage but are considered unsightly.

These Arctiid moths are native and widely distributed. They have a wide host range (85 species in US - Shetlar). Trees commonly infested in Oregon include walnut, fruit trees, and cottonwood, and other hosts include maple, pecan, American elm, hickory, willow, alder, madrone, persimmon and sweetgum (Shetlar, Johnson and Lyon 1991).

They can be distinguished from tent caterpillars in how they enclose themselves in their web along with their food, usually a branch or twig with leaves while tent caterpillars can be found outside their much smaller web. Two races occur in North America and are named for their morphological differences, the blackheaded race and the redheaded race.

Fall webworm overwinters in the pupal stage in the ground, leaf litter, or under bark. Adults emerge in summer (late May-July in Ohio). Eggs hatch in about a week and development of the caterpillar to maturity is about six weeks.

Management options include physical removal of the nests, conservation of natural biological control, use of applied biological control particularly Bt applications; and the use of foliar and systemic registered chemical controls.

Johnson and Lyon (1991) report over 50 species of parasites and 36 species of predators of this pest acting against fall webworm in America.

Sourakov, A. and T. Paris. 2011. Fall Webworm. UF/IFAS Featured Creatures. <10 August 2018>

Douce, K. The Bugwood Network Fact sheet: Fall Webworm
Hyphantria cunea (Drury)

L.L. Hyche, Auburn University. FALL WEBWORM: A Guide to Recognition and Habits in Alabama. Nice pictures at this site.

Johnson, W.T. and H.H. Lyon. 1991. Insects that Feed on Trees and Shrubs. Cornell University Press. Ithaca and London. 560 pp.


Fall webworm webbing on cherry
fall webworm webbing
Fall webworm caterpillars and webbing in black walnut
fall webworm caterpillars and webbing
Feeding within web defoliates branch
fall webworm damage
Fall webworm caterpillars and fecal pellets in webbing
Fall webworm caterpillars
Small webworm larvae can be seen through the webbing on an apple branch
Fall webworm larvae on apple branch

Fall webworm caterpillar
Fall webworm caterpillar
Website editor:
Robin Rosetta

Page last modified 8/9/11


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