New Online Resource Will Help Control the Asian Longhorned Beetle
By Stacy Kish
The Asian longhorned beetle, Anoplophora glabripennis, is a wood-boring insect that is capable of destroying 30% of the urban trees in the United States at an economic loss of $669 billion. Infestations of this invasive beetle have been found in Ohio, New York, New Jersey, Massachusetts, and Illinois, and they have been shown to feed on more than 100 different tree species, with a preference for maples, poplars, aspens, cottonwoods, and willows.
Now a new, open-access article in the Journal of Integrated Pest Management (JIPM) provides a comprehensive overview of the ALB, including a review of its biology, life stages, distribution, ecology, and methods of detecting and controlling it.
“There have been several reviews of ALB that were more for scientists, but this one is more for managers — people who are dealing with them,” said co-author Melody Keena, a research entomologist with the U.S. Forest Service. “This is a good summary of the scientific backing for everything the cooperative eradication programs are doing. They can point the public to this document for more information, especially because it’s written for JIPM in language that non-scientists can understand.”
As its name implies, the invasive ALB is originally from Asia. Adults are quite large, measuring up to 39 millimeters in length, and their long antennae can be as much as twice the length of their bodies.
“These are big beetles,” Dr. Keena said. “Some of the larvae can be the size of a woman’s little finger. They can be substantial, and a single ALB larva can consume 1,000 cubic centimeters of wood.”
The supplementary tables in the JIPM article will be particularly helpful for managers, according to the authors. The first lists nearly 160 different trees on which the ALB can feed, oviposit, or complete development under field conditions. Another lists tree species that are not considered to be ALB hosts, so they may be good choices for replanting efforts.
Because of their size, one might think that detecting the ALB would be easy. However, they tend to stay quite high in the trees, which means that teams of trained surveyors or tree climbers are required to look for the telltale signs of an infestation, which include boreholes, exit holes, frass, and sap oozing from tree wounds. Other means of detection include sniffer dogs and pheromone traps.
When detected, the most effective means to eradicate the beetle from an area is to burn or chip the infected trees and grind the stumps. However, this approach is costly and may be controversial with the public.
One possible control method that may be promising in the future involves spraying an entomopathogenic fungus (a fungus that kills insects) on tree trunks and branches, along with trail pheromones that would be used to lure them to the trees.
“It’s the old idea of attract and kill,” Dr. Keena said, “but it’s got a little ways to go” as scientists at Cornell University work out different spray formulations and how to use the pheromone with it.
The eradication programs and other control methods take advantage of the ALB’s tendency to stay in a tree for long periods of time.
“They don’t love to fly and will often stay with one tree as long as it’s viable,” Dr. Keena said. “So they don’t spread as much as other insects, like the emerald ash borer.”
In China, they have taken advantage of this by using some trees as “traps” in a forest to attract the beetles. Then after infestation, they are cut down and burned before the adults emerge.
In its natural habitat, the beetle is kept in place by host tolerance of native trees and by natural enemies. However, the idea of introducing another species into a non-native habitat is perhaps even riskier than the initial unintentional introduction of the beetle, so scientists are looking for parasites of native wood-boring beetles to determine their efficacy on the ALB. The jury, however, is still out on this approach.
Most commonly, the public is the first to notice, investigate, and alert officials about infestations. This is important because the sooner these beetles are detected, the better.
“We highlighted early detection as an important part of the eradication program because the faster they are found, the less they have spread,” Dr. Keena said. “Traps baited with pheromones and plant volatiles (plant smells) that our research group developed are a newer tool that is helping to detect this beetle, but all infestations found in the U.S. to date have been spotted by the public and brought to the managers’ attention.”
The authors hope that forest managers and others will put this insect profile to use.
As Dr. Keena said in an interview, “When JIPM’s Co-Editor-in-Chief Marlin Rice invited me to write this article, I invited Peter Meng, a Pennsylvania State University graduate student to take the lead, because JIPM articles allow graduate students to take a lot of their literature searches results and thesis introductory material and put it into a format that’s actually used by somebody.”
The failure to control the spread of the ALB could be disastrous for native forests and urban trees in the U.S. If you suspect the ALB to be in your area, contact your local forestry office for assistance.
Read more at:
– Asian Longhorned Beetle (Coleoptera: Cerambycidae), an Introduced Pest of Maple and Other Hardwood Trees in North America and Europe
Though, I am wondering why Dr. Keena couldn’t have just said “the size of a little finger”.
The pinky, as opposed to the ring finger or the thumb.
I think Chaos realm is trying to cause a fuss over the language of using gendered language.
Well, perhaps she is comparing it to her finger, and men’s hands do tend to be larger than a woman’s hand.
Well, whether adding insect-killing fungi is the right choice (for example: will they kill the remaining bees that survived the onslaught of varroa and neonicotinoids?) I truly wonder. Also “… capable of destroying 30% of the urban trees in the United States at an economic loss of $669 billion …” sounds rather impressive, but I suspect this is the potential “whole lot” of existing trees that could be attacked? Which, epidemiologically, might mean, only a third would actually be truly killed until the ecological system comes to a new equilibrium where some trees develop better resistance, other, resistant, species take over the places thus emptied and certain predators would eventually specialize and decimate this new source of food etc. We probably can only draw out these processes but globalization will bring a new equilibrium of species, once historians look back from, say, three hundred years from now. “Oviposit” – learned a new word today to be able to show of my “erudition” …
Re bee effects: several studies regarding impact of Beauveria on honeybees have been conducted. In 1990s I conducted two such studies with the commercial B bassiana GHA, the first spraying all the workers from replicate colonies with field rate 3 times at 5-day intervals. Colonies included ones with Ascosphera, and colonies spanning a quantified range of hygienic behavior. Second test was one application at 5X the high label rate of the GHA (1×10^14 spores/acre). In both instances no effect (30-day observation period) on foraging & worker bee turnover (they do have a finite lifespan), larval mortality, even when Ascosphera was present in the colony, and no Beauveria infections among the dead. A “happy bee” (able to be in its normal sociological environment, in contact with her queen, and able to behave ‘normally’) is a healthy, resistant bee. One result is that Canada has authorized use of bees to Vector GHA to flowering crops. One or two other Beauveria have shown similar lack of adverse effect.
I saw one of these many many years ago when my husband and I were driving back home to Texas from Louisiana. We were very close to the Texas border when I looked over at my husband, who was driving, and noticed a very large beetle, with very long antennae on his shoulder. I don’t know where it came from. It just sort of appeared there out of no where. Not knowing whether it bites or not (but still intrigued by it’s size & markings), I carefully managed to get it to walk onto a piece of paper (hoping it wouldn’t start flying, which I wasn’t sure if it had wings or not), took a few pictures (I still have the photos) of it & kind of just let it chill until we were able to set it free at a rest stop.