Emerald Ash Borer
MODERATEAgrilus planipennis
Overview
An invasive wood-boring beetle native to Asia that has killed hundreds of millions of ash trees across North America since its discovery in Michigan in 2002. Larvae feed on the inner bark, disrupting nutrient and water transport.
- Type
- Insect
- Severity
- MODERATE
- Source
- iNaturalist
Symptoms
Canopy dieback starting at the top of the tree, D-shaped exit holes in bark, serpentine larval galleries under bark, increased woodpecker activity, epicormic sprouting along the trunk
Affected Species
Geographic Spread
Treatments
Systemic Insecticide Trunk Injection
Trunk injection of emamectin benzoate (TREE-age) provides 2-3 years of protection. Most effective when applied before significant canopy loss. Requires a certified applicator.
Soil Drench Imidacloprid
Systemic insecticide applied as a soil drench around the base of the tree. Less effective on large trees (>20 inch DBH) due to slower uptake. Annual application required.
Biological Control with Parasitoid Wasps
USDA-approved release of parasitoid wasps (Tetrastichus planipennisi, Oobius agrili, Spathius galinae) that attack EAB larvae and eggs. Provides long-term population suppression but not individual tree protection.
Recommended Products & Tools
Helpful supplies for managing Emerald Ash Borer. Always read and follow label directions, and confirm a diagnosis before treating.
Soil drench for protecting ash trees with under ~50% canopy loss.
Knocks down soft-bodied pests like aphids, mites, and scale crawlers.
Smothers overwintering eggs and crawlers; dormant or summer rates.
Soil-applied protection taken up by the tree for season-long control.
Sharp, clean cuts to remove affected wood — a tree-care essential.
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Frequently Asked Questions
What is Emerald Ash Borer?
An invasive wood-boring beetle native to Asia that has killed hundreds of millions of ash trees across North America since its discovery in Michigan in 2002. Larvae feed on the inner bark, disrupting nutrient and water transport.
What are the symptoms of Emerald Ash Borer?
Canopy dieback starting at the top of the tree, D-shaped exit holes in bark, serpentine larval galleries under bark, increased woodpecker activity, epicormic sprouting along the trunk
Where is Emerald Ash Borer currently found?
Emerald Ash Borer is currently active in Connecticut, Delaware, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Maine, Michigan, Minnesota, Missouri, North Carolina, Nebraska, New Hampshire, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Virginia, Vermont, Wisconsin, West Virginia, District of Columbia, Arkansas, Colorado, North Dakota. It has been reported in 36 total states across the United States.
What plants are affected by Emerald Ash Borer?
Emerald Ash Borer affects Green Ash, White Ash. Susceptibility varies by species.
How do I treat Emerald Ash Borer?
Treatment options for Emerald Ash Borer include: Systemic Insecticide Trunk Injection, Soil Drench Imidacloprid, Biological Control with Parasitoid Wasps. Treatment approaches may include chemical, biological, cultural, and mechanical methods depending on the severity and context.
Compare with Similar Ailments
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