Brown marmorated stink bug
Halyomorpha halys
85 host plants
Last updated
You will spot brown shield-shaped insects about 1/2 inch long on fruit, leaves, and stems during late summer and fall. These bugs pierce plant tissue with straw-like mouthparts and suck juices, causing dimpling, distortion, and decay in fruit or seeds. Look for them on serviceberry, hawthorn, mahonia in warm microclimates.
Remove and destroy infested fruit or seed heads before bugs disperse to overwintering sites. Knock bugs off plants early morning when sluggish into soapy water. Protect high-value crops with row covers before bugs appear. Encourage parasitoid wasps by reducing broad-spectrum insecticide use. Organic spinosad provides control; chemical treatment rarely justified for ornamentals.
Quick Reference
The brown marmorated stink bug (BMSB) is an introduced pest species from Asia that is spreading quickly across the United States. Nymphs and adults feed on a wide variety of plant hosts. BMSB prefers to feed on fruit, seeds, and seed pods, but will also feed on stems and leaves of some hosts. Both adults and nymphs have piercing-sucking mouthparts and inject digestive enzymes into plant tissues to aid in feeding. On beans, BMSB damage can appear as discolored, sunken lesions or as warty or pimple-like growths on the pod surface. Inside the pod, whitish or brown spots develop, and seeds may be
Cultural Controls
- Pick and destroy BMSB egg masses or groups of young nymphs.
- While hand-picking adults may be somewhat effective in small gardens, manual control may not be very successful due to the wide host range and large numbers of BMSB in some areas.
- Catching adults and nymphs can be facilitated through net-sweeping, plant vacuuming or shaking the infested plant over a drop cloth.
- Some natural enemies feed on BMSB, including domestic chickens, praying mantids, and other predacious insects.
- While natural enemies may not be sufficient to provide complete control, avoid use of broad-spectrum insecticides which would harm populations of beneficial insects.
- When practical, plants may be screened with a floating row cover or similar barrier.