Most everyone is familiar with one or two invasive pests to Virginia such as the Asian lady bug or gypsy moth . Even more folks have likely had experience with invasive plants such as kudzu, honeysuckle, Asian bittersweet or tree of heaven (ailanthus).
However, with the enormous global trade in international goods, there are many more potential invasive insects and plants facing the health of our eastern forests. Many foreign invasives come into the U.S. via pallets where larvae have bored into the wood for a cozy trip overseas or have stowed away in packing materials. The nursery trade has also introduced quite a few problems. Border control agents can’t keep up with the volume of goods being shipped from overseas, don’t always recognize signs of potential problems or can’t recognize them as some pathogens are only identified in laboratories and the presence is only determined after damage occurs.
For two days in early February, the Virginia Association of Forest Health Professionals (VAFHP) holds an annual meeting to discuss these “pests of concern” and learn more about what can be done to control them to protect native habitats.
A prime example of such a pest that really creeped everyone out at the 20th annual conference recently held in Staunton, Virginia was the Brown Marmorated Stink Bug, presented by Starker Wright from the USDA Agricultural Research Service.
If you live in the Shenandoah Valley, you know the Brown Marmorated Stink Bug (BMSB), aka Halyomorpha halys.
This slow-moving shield-shaped insect loves your house/barn/outbuilding/outhouse in the winter.
In addition to being a household pest – they begin seeking indoor overwintering sites about September 21 – the BMSB poses an enormous economic impact to agricultural crops. They feed on cherries, peaches, apples, grapes, soybeans, wheat, tomatoes, eggplant and many other small vegetable crops. In fact, they have over 300 host plants and have two generations a year in the mid-Atlantic U.S., with females laying about 400 eggs per cycle. No native predators have as of yet come forward to save the day. The rise of the BMSB in the U.S. has been quick – it was positively identified in Allentown, PA in 2001 and severe crop injury was reported in WV, MD, NJ, DE and VA in 2010.
“The larvae are the primary threat, they don’t have to do a lot of feeding to cause a lot of damage,” said Mr. Wright.
And here is where the big picture comes in – we have lots of invasive plants established in mid-Atlantic which are native to Asia such as ailanthus, empress tree, kudzu and wineberries – and not surprisingly, the BMSB seek these species out for overwintering habitat (if they can’t find your house). However, as is typical of invasives, they are flexible invaders and they also will make do with our native boxelder and other maple species, white ash and hackberry trees. This means they are adapting well to this area.
Research is underway to determine the best control techniques for this pest.
In other updates, speakers provided information on Thousand Cankers Disease (kills black walnut trees and which has been positively identified in the Richmond area), Asian long-horned beetle (primarily targets maples), and sudden oak death (kills many species) and the hemlock woolly adelgid (kills just hemlock).
To help balance out the sense of despair that the invasives are going to irreparably damage our natural ecosystem, the conference organizers planned some presentations which conveyed good news: the emerald ash borer has not extended its range in the last year, there is some hope on the horizon with a beetle which may help control the invasive tree of heaven, the Virginia Department of Conservation and Recreation is going to publish a fabulous new book entitled the Flora of Virginia and Casey Trees is busy planting trees in Washington, DC.
For more information on this excellent organization which helps keep those interested in the ecology of the eastern forests informed, go to http://vafhp.org/.
UPDATE 11/1/17: An article ‘Eight Simple Home Remedies to Get Rid of Stink Bugs’ has just been published with suggestions on ways to keep these pests from getting in your house, ways to trap them if they do get in and ways to eliminate them using natural methods.