Emerald Ash Borer
Additional Resources
General Information on Emerald Ash Borer (EAB)
Pest Status | Distribution | Monitoring | Where to Report | References
Please visit the emerald ash borer webpage for information on the pest description, life history, and management.
Pest Status
- Emerald ash borer (Agrilus planipennis) pest only attacks ash trees (Fraxinus spp.) and has been confirmed in Colorado. Since its discovery in North America, EAB has killed millions of ash trees and caused hundreds of millions of dollars in financial losses for municipalities, property owners, nursery operations, and forest product industries. This pest can spread long distances through the transport of infested wood.
Larva of emerald ash borer. Image credit: David Cappaert, Bugwood.org
Distribution
- Emerald ash borer is native to Asia, specifically China, Mongolia, North Korea, South Korea, Japan, Taiwan, and the Russian Far East.
- Emerald ash borer is an invasive species in North America where it was first discovered in Michigan in 2002. As of 2023, EAB has been detected in Colorado and 35 other states.
D-shaped exit holes created by adult EAB as they emerge from the host tree. Image credit: Daniel Herms, The Ohio State University, Bugwood.org
Monitoring
Purple prism traps
- Description
- These traps consist of three 14” x 24” panels with a sticky compound for capturing EAB adults. Each panel has several holes for attaching lures (will provide an image). The lure should not be covered with duct tape.
- For EAB monitoring, one pouch of (Z)-3-hexanol lure is recommended per trap. Please note that these lures must be stored in a freezer prior to deployment and kept in coolers during transport.
- Warning: The chemical emitted by these lure pouches may pose safety concerns in confined spaces with poor ventilation.
- Timing
- According to research, EAB adults emerge after 450 growing degree days (base 50°F). It is recommended that traps be placed just prior to this threshold. Lures should be replaced just before the 60-day expiration date. Traps should be inspected for adult EAB during each lure replacement, and traps should not be removed before 1,500 growing degree days. If traps are covered with excessive debris, the sticky compound can be scraped from the trap surface using a trowel or putty knife. Sticky compound can be added with a paint roller or trowel.
- Location
- These traps are deployed a minimum of five feet above the ground in the lower to mid canopy of ash trees with a diameter of 8” or greater. They should be located on the sunny side of the tree.
Purple prism trap suspended from a tree. The trap contains a lure for attracting emerald ash borer adults, and the panels are coated with a sticky substance for capturing the beetles. Image sourced by Wikipedia.org
Lindgren funnel traps
- Description
- These traps are made of 12 green plastic funnels, with green dome-shaped top and a plastic collection cup at the bottom. The funnels are pre-coated with a Fluon solution, which reduces friction to assist in the capture of EAB. Minor assembly may be required.
Lindgren funnel trap suspended from a tree. Each of the funnels is coated with a fluon solution, which assists with capturing beetles in the collection container at the bottom. Image credit: Kenneth E. Gibson, USDA Forest Service, Bugwood.org
Where to Report Findings
Suspicious insects and feeding injuries can be reported to the CDA website or emailed to CAPS.program@state.co.us
Note: It is recommended to take high quality photos of suspicious insects and/or feeding injuries.
References
References
USDA. 2023. Emerald Ash Borer. United States Department of Agriculture – Animal and Plant Health Inspection Service. Available https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/emerald-ash-borer#:~:text=The%20emerald%20ash%20borer%20(Agrilus,in%20southeast%20Michigan%20in%202002.
CSFS. 2023. Emerald Ash Borer: A Green Menace. Colorado State University – Colorado State Forest Service Available https://csfs.colostate.edu/forest-management/emerald-ash-borer/
USDA. (n.d.). Emerald Ash Borer Survey Guidelines. United States Department of Agriculture – Animal and Plant Health Inspection Service. Available https://www.aphis.usda.gov/plant_health/plant_pest_info/emerald_ash_b/downloads/eab-survey-guidelines.pdf
Need Insect Identification Help?
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