Red foliage

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. 

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Defoliators

California Oakworm

Phryganidia californica

More information coming soon

Douglas Fir Tussock Moth

Orgyia pseudotsugata

More information coming soon

Douglas fir tussock moth, William M. Ciesla, Forest Health Management International, Bugwood.org
Douglas fir tussock moth, William M. Ciesla, Forest Health Management International, Bugwood.org

Douglas fir tussock moth

Douglas Fir Tussock Moth, William M. Ciesla, Forest Health Management International, Bugwood.org
Douglas Fir Tussock Moth, William M. Ciesla, Forest Health Management International, Bugwood.org

Douglas Fir Tussock Moth

Douglas fir tussock moth, William M. Ciesla, Forest Health Management International, Bugwood.org
Douglas fir tussock moth, William M. Ciesla, Forest Health Management International, Bugwood.org

Douglas fir tussock moth

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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.

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Location: Europe, US, California

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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.

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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.

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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).

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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, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org
Gypsy moth, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org

Gypsy moth

Gypsy moth larvae, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org
Gypsy moth larvae, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org

Gypsy moth larvae

Gypsy moth, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org
Gypsy moth, USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org

Gypsy moth

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Learn More

Fruit Tree Leafroller

Archips argyrospila

More information coming soon

Fruit tree leafroller, USDA Forest Service - Region 8 - Southern , USDA Forest Service, Bugwood.org
Fruit tree leafroller, USDA Forest Service - Region 8 - Southern , USDA Forest Service, Bugwood.org

Fruit tree leafroller

Fruit tree leafroller, USDA Forest Service - Region 8 - Southern , USDA Forest Service, Bugwood.org
Fruit tree leafroller, USDA Forest Service - Region 8 - Southern , USDA Forest Service, Bugwood.org

Fruit tree leafroller

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Pandora Moth

Coloradia pandora

More information coming soon

Pandora moth, USDA Forest Service , USDA Forest Service, Bugwood.org
Pandora moth, USDA Forest Service , USDA Forest Service, Bugwood.org

Pandora moth

Pandora moth larvae, USDA Forest Service , USDA Forest Service, Bugwood.org
Pandora moth larvae, USDA Forest Service , USDA Forest Service, Bugwood.org

Pandora moth larvae

Pandora moth, USDA Forest Service , USDA Forest Service, Bugwood.org
Pandora moth, USDA Forest Service , USDA Forest Service, Bugwood.org

Pandora moth

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Ponderosa Pine Tip Moth

Rhyacionia zozana

More information coming soon

Ponderosa pine tip moth, Donald Owen, California Department of Forestry and Fire Protection, Bugwood
Ponderosa pine tip moth, Donald Owen, California Department of Forestry and Fire Protection, Bugwood

Ponderosa pine tip moth

Ponderosa pine tip moth damage, Donald Owen, California Department of Forestry and Fire Protection,
Ponderosa pine tip moth damage, Donald Owen, California Department of Forestry and Fire Protection,

Ponderosa pine tip moth damage

Ponderosa pine tip moth, Donald Owen, California Department of Forestry and Fire Protection, Bugwood
Ponderosa pine tip moth, Donald Owen, California Department of Forestry and Fire Protection, Bugwood

Ponderosa pine tip moth

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Silver Spotted Tiger Moth

Lophocampa argentata

More information coming soon

Silver spotted tiger moth, USDA Forest Service - Forest Health Protection Intermountain Region - Ogd
Silver spotted tiger moth, USDA Forest Service - Forest Health Protection Intermountain Region - Ogd

Silver spotted tiger moth

Silver spotted tiger moth larvae, Cheryl Moorehead, Bugwood.org
Silver spotted tiger moth larvae, Cheryl Moorehead, Bugwood.org

Silver spotted tiger moth larvae

Silver spotted tiger moth, USDA Forest Service - Forest Health Protection Intermountain Region - Ogd
Silver spotted tiger moth, USDA Forest Service - Forest Health Protection Intermountain Region - Ogd

Silver spotted tiger moth

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Spotted Lanternfly

Lycorma delicatula

More information coming soon

Learn More

Spotted lanternfly, Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org
Spotted lanternfly, Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org

Spotted lanternfly

Spotted lanternfly, Eric R. Day, Virginia Polytechnic Institute and State University, Bugwood.org
Spotted lanternfly, Eric R. Day, Virginia Polytechnic Institute and State University, Bugwood.org

Spotted lanternfly

Spotted lanternfly, Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org
Spotted lanternfly, Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org

Spotted lanternfly

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Western Spruce Budworm

Choristoneura freeman

More information coming soon

Western spruce budworm, USDA Forest Service - Region 4 - Intermountain , USDA Forest Service, Bugwoo
Western spruce budworm, USDA Forest Service - Region 4 - Intermountain , USDA Forest Service, Bugwoo

Western spruce budworm

Western Spruce Budworm, Ladd Livingston, Idaho Department of Lands, Bugwood.org
Western Spruce Budworm, Ladd Livingston, Idaho Department of Lands, Bugwood.org

Western Spruce Budworm

Western spruce budworm, USDA Forest Service - Region 4 - Intermountain , USDA Forest Service, Bugwoo
Western spruce budworm, USDA Forest Service - Region 4 - Intermountain , USDA Forest Service, Bugwoo

Western spruce budworm

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