"Fostering education on the pests of California forests since 1951."
Many different species of defoliators currently threaten California forests. Some native, some not, defoliators are adult and larval insects that strip all the leaves or needles from a tree or shrub. Defoliation interferes with plant photosynthesis causing intesnse damage and or death.
Defoliators
California Oakworm
Phryganidia californica
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Douglas Fir Tussock Moth
Orgyia pseudotsugata
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Douglas fir tussock moth
Douglas Fir Tussock Moth
Douglas fir tussock moth
Gypsy Moth
Lymantria dispar
The gypsy moth (GM) is a pest that voraciously feeds on the leaves of trees and shrubs, threatening residential settings, forests and agricultural tree crops.
Location: Europe, US, California
Impact Significance: Gypsy moth caterpillars feed on hundreds of kinds of plants and are capable of defoliating trees at an alarming rate. A single gypsy moth caterpillar can eat up to one square foot of leaves per day. In the northeastern United States, millions of these caterpillars emerge each spring and devour large swaths of forest and foliage.
Hosts: Young caterpillars feed primarily on oaks, aspen, birch, willows and alder, and older caterpillars feed on a broader range of trees including cedar, pine, spruce and fir. Common California species such as manzanita, western hemlock, Douglas fir and live oak are also prone to damage by this pest.
Biology: The strain of gypsy moth established in the U.S. is commonly called the European gypsy moth (EGM). This is to distinguish it from a strain that exists in Asia, called the Asian gypsy moth (AGM).
Damage: When trees are repeatedly defoliated, they are rendered more susceptible to other pests and diseases, potentially leading to tree death and an increased potential for fire and erosion.
Gypsy moth
Gypsy moth larvae
Gypsy moth
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Fruit Tree Leafroller
Archips argyrospila
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Fruit tree leafroller
Fruit tree leafroller
Pandora Moth
Coloradia pandora
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Pandora moth
Pandora moth larvae
Pandora moth
Ponderosa Pine Tip Moth
Rhyacionia zozana
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Ponderosa pine tip moth
Ponderosa pine tip moth damage
Ponderosa pine tip moth
Silver Spotted Tiger Moth
Lophocampa argentata
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Silver spotted tiger moth
Silver spotted tiger moth larvae
Silver spotted tiger moth
Spotted Lanternfly
Lycorma delicatula
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Spotted lanternfly
Spotted lanternfly
Spotted lanternfly
Western Spruce Budworm
Choristoneura freeman
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Western spruce budworm
Western Spruce Budworm
Western spruce budworm