By: Joe Boggs, OSU Extension
Asian Longhorned Beetle (ALB) (Anoplophora glabripennis) is potentially the most devastating non-native pest to have ever arrived in North America. The beetle kills trees belonging to 12 genera in 9 plant families. This includes Acer (all maple species); Aesculus (horsechestnuts and buckeyes); Ulmus (elms); Salix (willows); Betula (birches); Platanus (Sycamore/Planetrees); Populus (Poplars); Albizia (Mimosa); Cercidiphyllum (Katsura); Fraxinus (ashes); Koelreuteria (goldenraintree); and Sorbus (mountainash).
Maples are the most preferred host. The ripple effect of losing native maples across many forest ecosystems also means the potential loss of other plant species as well as animal species that are dependent upon the overall health of those ecosystems.
Successful eradication of ALB is essential to avoiding a catastrophic loss of trees as well as habitat on a scale never before seen in the U.S. That’s why the announcement on October 10, 2019, by the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) in coordination with the New York State Department of Agriculture and Markets, New York State Department of Environmental Conservation, and New York City Department of Parks and Recreation is so important. ALB has been eliminated in the New York City boroughs of Brooklyn and Queens.
This was a hard-earned victory in the long battle to eliminate ALB from the U.S. because Brooklyn was “ground zero.” The non-native beetle was first detected in the U.S. infesting Norway maples in Brooklyn in 1996. Additional infestations were later found in Long Island, Manhattan, Staten Island, and Queens. Manhattan and Staten Island were declared beetle-free in 2013. Work continues towards eradicating ALB in Long Island. However, the announcement means the 137 square miles that were previously regulated for ALB in New York State are now reduced to 53-square miles in Nassau and Suffolk counties on Long Island.
You can read the complete press release by clicking on this hotlink: https://content.govdelivery.com/accounts/USDAAPHIS/bulletins/2654885
Remain Vigilant!
The dedicated professionals with the ALB Cooperative Eradication Program in Ohio which includes the USDA APHIS and the Ohio Department of Agriculture (ODA) have also scored their own victories. ALB was first detected in Ohio near Bethel in Tate Township, Clermont County, in June 2011. “Satellite” infestations were found in Monroe Township in September and in Stone Lick Township in 2012; both were declared eradicated last year.
Work is continuing on eradicating ALB from Tate Township and the adjoining East Fork State Park / East Fork Wildlife Area. However, past experience dictates that we should remain vigilant for ALB not only in the immediate vicinity but also elsewhere in the U.S. That’s because our Ohio ALB infestation arrived directly from China; the beetles did not come from New York. The same is true for other ALB infestations in the U.S. Beyond the associated satellite infestations sometimes found near a new ALB discovery, the beetle has not been moved or spread naturally over great distances within the U.S.
Early detection is critical to the successful eradication of ALB both in terms of time and money. Never believe ALB is “somewhere else.” ALB can pop-up anywhere, even in our own backyards.
Here are some tips on what to look for:
- Focus on Maples. ALB will attack trees belonging to 12 genera; however, maples (Acerspp.) are by far the most preferred host.
- Branch Breakage. ALB larvae tunnel through and feed on the wood (xylem) of trees. This weakens branches causing them to break. Unusually heavy branch breakage on living maple trees should be investigated!
- Holes: The “Pencil Test.” The big beetles typically emerge from deep inside the wood of a tree (xylem), so the round adult emergence holes extend deep into the tree. Inserting a #2 pencil into the holes will reveal the depth of the emergence holes. However, trees may close the exit holes with callous tissue.
- Pits in the Bark. ALB females chew a concave pit through the bark to the xylem where they lay a single egg. The “oviposition pits” may weep sap during the season. However, usually close the pits relatively quickly, so you may only see rounded wounds.
- Heavy Woodpecker Damage. ALB larvae live deep inside the xylem. Woodpeckers excavate deep holes in search of these large tasty meat morsels. Look for deep woodpecker damage on living tree stems.
- Frass: Small Wood Shavings. ALB produces small wood shavings as they emerge from trees or as the females chew oviposition pits.
- Bark Cracking. Larval feeding damage may stimulate trees to produce callous tissue then woundwood beneath the bark. The expanding wound response tissue lifts the overlaying bark producing cracks and fissures.
- Big Beetles. ALB is a very large beetle. We are at the end of the “beetle season” in Ohio; however, some beetles may still be found wandering about. It’s also important to monitor insect collections submitted as school or 4-H projects. Larvae, which are known as “roundheaded borers,” that are found inside living tree trunks and branches may signal an ALB infestation.
If you find any of these ALB indicators, report it. Give the ALB professionals a chance to investigate. In fact, if you find ANY suspicious signs or symptoms, report it! There is no harm if it turns out not to be ALB; there is great harm if it is ALB and it’s not reported.
You can report by phone by calling 1-866-702-9938, or 513-381-7180. You can also report online by clicking the hotlink below:
https://www.aphis.usda.gov/aphis/resources/pests-diseases/asian-longhorned-beetle/report-it