Emerald Ash Borer: What do birds have to do with it?
By Katherine Manaras
By now you’ve seen the lantern-like purple triangles hanging in trees along the roads. Maybe you’ve also heard what they are: they’re insect traps the Forest Service set to monitor the advancement of the Emerald Ash Borer (EAB). EAB - an exotic beetle native to Asia - attacks native ash trees, and is thought to be a major threat to ash trees in Vermont, even though it has not yet been detected here. The bug was first detected in Michigan in 2002, and has been marching east ever since. It was recently detected in Massachusetts. So, it's on its way.
The Vermont Department of Forests, Parks and Recreation (FPR) is reminding landowner and managers not to panic and cut down all the ash in their woods. Rather, it’s important to maintain diverse and healthy forests in the face of EAB and other threats. Read FPR’s recommendations here.
The EAB tragedy does have a hero. And, you guessed it: the hero is a bird! Woodpeckers – particularly hairy and downy woodpeckers - are among the most important natural enemies of the pest, and they ate 90% of the EABs in one study area. Woodpecker damage on trees can also help people identify infestations, since it is conspicuous much earlier than the resulting dieback.
These are some of the important reasons to keep woodpeckers in our woods! Improving habitat for hairy and downy woodpeckers is similar to providing for yellow-bellied sapsucker (who represents woodpeckers in the Birder’s Dozen). Key management guidelines are:
- Manage for at least 4 hardwood snags per acre 12 inches in diameter or larger. The bigger, the better.
- Retain declining trees to recruit future snags. Aspen, paper birch, red maple and sugar maple are good choices.
- Retain all cavity trees with evidence of use by woodpeckers for feeding or nesting.
- Maintain interior forest conditions by limiting fragmenting roads and permanent openings
- Contact Audubon or your county forester with questions about managing with EAB-eating woodpeckers in mind.
You can help your community prepare for and respond to infestations of EAB and other invasive forest pests by joining a local volunteer effort. To become a Beetle Detective, Wasp Watcher or First Detector, click here.
Katherine Manaras is a Conservation Biologist with Audubon Vermont. The article was originally published in Audubon Vermont's Friends of Forest Birds Newsletter. Text reprinted with permission.