Did you know that August is National Tree Check Month? That’s because it’s the peak time of year to find invasive bugs like citrus longhorned beetles, emerald ash borers and other aggressive wood-boring insects.
Take a quick peak at your trees to see if you spot any of these invasive bugs. First indications of invasive insect damage to trees include sudden dieback or death among trees that are otherwise vigorous and healthy. If you see this, look further for sawdust, exit holes or actual beetles. If you have a pool, also check your pool skimmers and filters for these bugs.
If you spot or think you spot signs of them, take photographs and report the find immediately online at www.invasivespecies.wa.gov/report.shtml, where you can access the reporting form or download the free WA Invasives mobile app. If the insect can be captured or collected, each county has a Washington State University Extension Office and Master Gardener Program that can help identify suspect insects. Ours is right in Puyallup–click here for details.
The citrus longhorned beetle, a close relative of the infamous invasive Asian longhorned beetle is a large shiny black beetle with white spots. At this time of year, adult beetles emerge from trees, leaving large, circular exit holes about 5/8 inch in diameter. The beetle can feed on and kill a variety of hardwood trees including apple, maples, oaks, willows and poplars. Washington has a number of look-alike native beetles and it takes a trained eye to distinguish them, so residents are asked to provide any suspect beetles to one of the agencies mentioned above. In 2001 this species was detected in Tukwila and was eradicated successfully in a cooperative effort between the Washington State Department of Agriculture and U.S. Department of Agriculture. Photo from Plant Protection Service, Bugwood.org
The emerald ash borer is a shiny, half-inch long, metallic green beetle. Adults begin flying in June and will continue through August as they emerge from ash trees, their primary host. The exit holes in the tree’s trunk are about a quarter-inch wide and have a distinctive D-shape. This species has been moving westward as campers move firewood far from where they bought it and recently was discovered in Boulder, Colorado. Photo from Debbie Miller, USDA Forest Service, Bugwood.org