Unfortunately, she says, the trap catches didn’t correlate to damage levels within the orchard.
“We’ve learned so much this summer, but there’s so much to learn still,” she says.
Get to know the brown marmorated stink bug
The brown marmorated stink bug, a native of China and east Asia, is the size of a green stink bug—about 0.6 inches long. Known scientifically as Halyomorpha halys, the brown marmorated stinkbug has the typical shield shape of other stink bugs. Adults are brownish with characteristic white or off-white antennae segments and darker bands on the membranous, overlapping part at the rear of the wings. They have red eyes.
The early instars, or life stages, are mostly reddish yellow and grow to more resemble adults as they reach the latter instars.
And as its name implies, the brown marmorated stink bug emits a foul-smelling chemical when squeezed or squished. Some have compared the odor to strong cilantro, stale gym socks or skunk.
Since the pest was first confirmed in Allentown, Pa., in 2001, it has been found in 23 other states coast to coast.
Growers in the East reported spotty damage in 2009. During the 2010 season, growers and homeowners in the Northeast and Mid-
Atlantic reported widespread damage. A few apple and peach growers reported fruit injury of 80 percent or greater.
“This is the worst pest I’ve seen in over 40 years, including grad school,” says Galen Dively, an emeritus entomology professor at the University of Maryland in College Park. “There are just so many hosts. We don’t know a lot about it because it’s an invasive species, so we’re kind of operating blindly.”
Ever-increasing host range
The host range is extensive and growing.
Among the hosts documented so far are apples, stone fruit, grapes, tomatoes, peppers, egg plants, cucurbits, corn (both field and sweet), green beans and soybeans. It also favors ornamental plants and trees, including roses, honeysuckle, Paulonia, Norway maple, catalpa and crabapple.
This new stink bug appears to have two generations per year in the Mid-Atlantic states, says Tracy Leskey, a research entomologist at the Agricultural Research Service’s Appalachian Fruit Research Station in Kearneysville, W.Va.
In China, researchers report up to five generations annually.
It frequently migrates from wooded areas into agricultural fields, with heavier populations initially seen along field or orchard edges.
“The green stink bug barely overwinters in our area,” Dively says. “Usually you see this [green] stink bug late in the season because it takes a while to build up.