The Asian brown marmorated stink bug (Latin: “Halyomorpha Halys”) continues to increase its habitat in Minnesota since being detected in Ramsey County in 2010, state agriculture officials say, with confirmed sightings now reported in Anoka, Carver, Chisago, Dakota, Hennepin, St. Louis, Washington and Winona counties during the past year.
The Minnesota Dept. of Agriculture (MnDOA) has issued an “Invasive Pest Alert” for the insect, which spreads to new areas by flying or by stowing away on shipping containers or vehicles. The insects band together in large groups to survive the winter months. The over-wintered adults emerge in March and April, and normally produce offspring in June.
Adults feed on fruits, vegetables and soybeans, and the MnDOA cites reports from farms in the eastern U.S. that state that large infestations have led to significant damage in fruit orchards, where feeding results in necrotic spots on the skin of hanging fruit and attached leaves. One generation is produced in the normal life cycle every year.
Adults are one-half inch in length, with a shield-shaped carapace with “marbled” brown coloration (See attached photo), with alternating black and white patterns on the margins of the abdomen and dark-colored antennae with white alternating bands.
The insect lays clusters of 20 to 30 white or light green eggs on the undersides of leaves, hatching nymphs with red or orange markings that grow darker as they age.
The species is thought to have migrated from China, Korea and Japan on shipping containers and began spreading in several of the Mid-Atlantic States and Oregon after 2001. Currently, 36 states have reported confirmed sightings of the invasive species at the present time.
There is currently no totally effective means of combating the spread of the insect, as insecticides are only partially successful. Once a treatment wears off, new insects replace the ones removed by the chemical treatment.
The Asian variety is often found in homes, producing a “foul-smelling” scent effusion when disturbed. Native stink bugs rarely if ever invade homes, officials say.
Residents are asked to report potential sightings to the Mn Dept. of Agriculture through the “Arrest the Pest” program. The service can be contacted on-line at Arrest.the.Pest@state.mn.us, of via voicemail at 1-888-545-6684.