Friends, Pittsburghers, park enthusiasts, lend us your eyeballs.
There’s a Pennsylvania-wide game of nature “Where’s Waldo?” happening right now, and we invite you to play along. Rather than searching for a man in a red-and-white striped getup, though, we’re all keeping our eyes peeled for the white-and-black striped Asian longhorned beetle.
What is the Asian longhorned beetle?
An invasive, or non-native, species of beetle originally from Korea, China, and Japan, the Asian longhorned beetle (ALB) migrated to the United States sometime in the 1990’s as a stowaway in shipping pallets. Since then, slowly but steadily, the insect has really sunk its mandibles into U.S. forests.
Part of what makes the Asian longhorned beetle such a large threat is its diet. A pickier eater would be more predictable: If it loved just one particular tree, we would know to monitor that tree type and watch for infestation. However, even though ALB is partial to red maples, it will make do with a wide range of host tree species: horsechestnuts, buckeyes, birches, planes, sycamores, willows, elms, boxelders, and other maples.
Once it finds a tree to inhabit, females burrow under the bark to lay eggs. After hatching, larva burrow throughout the tree to feed on the tree’s sugars and nutrients, eventually killing its leafy host. ALB is also a significant threat because it doesn’t respond to any known biological or chemical controls; once it infests a tree, that tree must be removed.
The stories of ALB infestation can be heart-wrenching. But, even though ALB has been found in surrounding Ohio, New Jersey, and New York, we don’t think it has found its way to Penn’s Woods quite yet. And that gives us a lot of hope.
This week, a grouping of exceptionally knowledgeable arborists and naturalists (plus a few of us amateurs) busted out binoculars for an Urban EcoSteward training on spotting signs of the Asian longhorned beetle in Frick Park. Many a success story (such as the oak wilt trees in Schenley Park) of invasive insect/plant and disease eradication starts with an alert citizen speaking up when they see an issue.
And here’s where we need your help!
The more people on the lookout for ALB, the better the chances of spotting this unwanted visitor before thousands of our street and park trees are threatened. Keep a sharp eye out for these signs:
Chomp marks. Mature Asian longhorned beetles have a distinct way of dining. They love eating the veins of leaves, as well as the bark of young twigs. Infestations typically start from the apex of the tree, so check for easy-to-spot dead/dying leaves at the top of the tree.
- Exit holes. Adult beetles exit the tree by burrowing. Check tree trunks for perfectly round holes, usually smaller than a dime.
Frass. Beetle burrowing can leave behind a sawdust, or frass, pile.
- The actual beetle. About .75 – 1.25 inches long, the adult beetle is black with irregular white spots on the wing covers. They have distinct black and white antennae that are longer than their body. Blue hairs on their legs can give them a bluish tinge.
Now for the most important part: If you see something, say something. Even if you’re not 100 percent sure of what you’ve found, snap a photo. If possible, catch the beetle in a jar or a box. Then, report your sighting by calling the PA Department of Agriculture at 1-866-253-7189 or by emailing them at firstname.lastname@example.org. If signs are spotted in the parks, please also let us know at email@example.com.
We’re not all doom and gloom over the Asian longhorned beetle (see photo below as proof). With watchful eyes and this week’s launch of the Park Tree Fund, we’re working hard to keep our park trees safe.
Much of the information from this blog was found through the University of Vermont’s stellar ALB resource pages. Read much more information about ALB here.