Brown Marmorated Stink Bug

• Sunken, discolored, cat-faced dimples on tomato and pepper fruit — the feeding site collapses as cells die beneath the skin
• Corky, pithy tissue just beneath the skin of damaged fruit when cut open
• White or light green blotches on bean pods and corn ears where the bug fed through the outer layer
• Distorted or aborted fruit on peppers and apples when bugs feed during fruit set
• Adults visible on plants: mottled brown shield-shaped bugs about 5/8 inch long, with alternating light and dark banding on the abdomen edge
• Distinct musty, cilantro-like odor when bugs are disturbed or crushed

Brown marmorated stink bug is an invasive species from Asia, first detected in Allentown, Pennsylvania in the late 1990s and now established across most of the United States. Adults overwinter in sheltered structures — including homes — and move into gardens and orchards when temperatures warm in spring. Females lay light green barrel-shaped eggs in clusters of about 28 on leaf undersides. There is typically one generation per year in northern states, two in warmer regions. The bug feeds on over 100 host plants, which makes population management especially challenging: bugs move freely between landscape trees, hedgerows, and vegetable gardens.

1. 01Inspect fruit-bearing crops two to three times per week from midsummer onward — catching damage early reduces total fruit loss
2. 02Hand-pick adults into soapy water in early morning when they are slow-moving; wear gloves to avoid the odor
3. 03Use exclusion netting over high-value crops such as peppers and tomatoes during peak bug pressure in late summer
4. 04Kaolin clay particle barrier applied to fruit can deter feeding on tree fruit; less practical for vegetable gardens
5. 05Trap crops of sunflower or sorghum at the perimeter can concentrate bugs where they are easier to manage
6. 06Pyrethrin or neem-based insecticides have some effect on nymphs but limited efficacy on adults with their thick cuticle — chemical control is generally last resort and short-lived given reinvasion from surrounding areas

If stink bug pressure is destroying a large portion of fruit crops every year despite exclusion efforts, contact your local extension office — monitoring trap networks and regional population data can help you understand whether pressure is seasonally high across your area.

• Brown Marmorated Stink Bug— Penn State Extension
• Brown Marmorated Stink Bug in the Home Garden— UC ANR Integrated Pest Management