| Emerald Ash Borer Survey |
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Order: Coleoptera
Family: Buprestidae
Scientific name: Agrilus planipennis Fairmaire
Common name: emerald ash borer (EAB)
Survey Objectives: To monitor the state for emerald ash borer. Each year ODA visually surveys more than a thousand ash trees across the state and in 2007 it has placed 40 trap trees in the Portland area at twelve sites. Surveying allows ODA to detect infestations when they are small and more easily eradicated.
Survey Technique: Visual Survey. Each trap site (gypsy moth, Japanese beetle, etc.) is a potential survey location for EAB. As ODA insect survey technicians check their traps they look for nearby ash trees to survey. They examine the trees for signs of EAB damage such as D-shaped exit holes, canopy dieback, suckering, and bark splitting.
Identification of Specimens (visual survey): Any possible damage is reported to an ODA entomologist for further inspection and possible monitoring.
Survey Technique: Trap Trees. It is difficult to detect EAB, as no dependable trap has been found to catch it yet. The best option available is to use a species of green ash from the Eastern U.S. that is highly attractive to the beetle and utilize them as a trap.
The ODA received a donation of forty 2.5-3” dbh green ash trees (Fraxinus pennsylvanicus) from J. Frank Schmidt Nursery and has planted them at 12 high-risk sites in the Portland metropolitan area. The trees were planted in the ground, staked for support, and then wounded by girdling them about 3 feet from the ground. Girdling consisted of peeling a 3.5” band around the tree, which causes stress-related chemicals to be released that are very attractive to EAB.
A 12” band of purple cellophane was then wrapped around the trunk immediately above the girdle and stapled to the tree. A sticky adhesive was applied to the cellophane in order to trap the beetles.
Trap servicing: Every two weeks from late May through early August, an insect survey technician will visit each tree and collect any suspect beetles and send them to the lab for identification. After September, the trees will be removed and their bark peeled. As the bark is peeled off, each tree will be examined for EAB larvae and their characteristic serpentine tunneling.
Identification of Specimens (trap tree survey): All suspect adult or larval beetles will be brought to the ODA insect lab in Salem for identification. Any damage suspected of being caused by EAB is reported to an ODA entomologist for further inspection and possible monitoring.
What if Detected: If EAB is detected or possible signs of EAB is detected then more surveying would take place in the area. If EAB is confirmed in the area, an eradication plan would follow.
Survey Results: After the end of each season survey results are published in the Plant Division Annual Report.
Photo Credits:
tree injection: David Cappaert, www.forestryimages.org
crown damage: Joseph O'Brien, USDA Forest Service, www.forestryimages.org
tree suckering: Minnesota Department of Natural Resources Archives, Minnesota Department of Natural Resources, www.forestryimages.org
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