🤢 Brown Marmorated Stink Bug (BMSB)

Halyomorpha halys · Hemiptera: Pentatomidae

BMSB is now established in 47 US states and continues spreading. The September exterior spray remains the single most effective prevention — but timing matters.

Stink BugInvasiveHemipteraFall Invader47 StatesAgricultural Pest
🤢
Risk Level
Fall Home Invader
📐 FIELD GUIDE ILLUSTRATION
Smoky Brown Cockroach (Periplaneta fuliginosa) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use anatomical labels above to confirm your identification.

📐 FIELD GUIDE ILLUSTRATION
Brown Widow (Latrodectus geometricus) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use anatomical labels above to confirm your identification.

📐 FIELD GUIDE ILLUSTRATION
Brown Banded Cockroach (Supella longipalpa) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use anatomical labels above to confirm your identification.

📐 FIELD GUIDE ILLUSTRATION
Brown marmorated stink bug (Halyomorpha halys) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use anatomical labels above to confirm your identification.

🔬
PestControlBasics Editorial Team
Reviewed by Derek Giordano · Updated 2026

🔍 Identification

14mm; shield-shaped; marbled brown/grey; diagnostic feature: alternating black and white bands on the abdomen margin and antennae (6 alternating segments visible). Adults also have a characteristic straight-edged abdomen (vs. curved in native stink bugs). Juveniles (nymphs): bright red-orange with black markings — strikingly different from adults.

🧬 Biology & Behavior

Invasive from Asia; first detected in Allentown, PA around 1996; now in 47 states. Produces aggregation pheromone that draws individuals to the same structures year after year. One generation per year; overwinters as adult in aggregations. 300+ host plant species including virtually all fruit and vegetable crops in eastern US.

⚠️ Damage & Health Risk

Agricultural losses ($37 million+ annually in the Mid-Atlantic alone); structural nuisance invasions; odor when disturbed; minor staining from defensive secretion if crushed. Psychological impact of large fall invasions.

🔧 DIY Treatment

The September exterior spray (bifenthrin or lambda-cyhalothrin) applied before aggregation is the only effective prevention. Seal exterior gaps. Yellow exclusion netting on high-value crops. Vacuum indoor individuals rather than crushing.

👷 When to Call a Pro

For persistent severe invasions, professional September application with commercial equipment provides better coverage than homeowner sprayers.

❓ FAQ

Why does the same house get stink bugs every year?
BMSB deposits aggregation pheromone on structures used for overwintering. This chemical signal persists and guides new generations back to the same buildings. The pheromone is why year-after-year invasions of the same house occur regardless of source insect population changes.
What's the best product for stink bug prevention?
Bifenthrin or lambda-cyhalothrin applied to south- and west-facing exterior surfaces in early September provides the best results. The timing matters more than the product — applying after aggregation begins is much less effective.

🗺️ Geographic Range & Distribution

FactorDetails
U.S. RangeAll 50 states
Regional DetailNorway rat: nationwide in urban areas. Roof rat: Southeast, Gulf Coast, Pacific Coast. Most active fall through spring.

📅 Treatment Timing Guide

Treating at the right time dramatically improves results. Pest control timed to the life cycle uses less product and achieves better long-term control.

PeriodAction
SpringInspection and perimeter treatment before pest season starts.
SummerActive monitoring and targeted treatments as needed.
FallPreventive treatment before overwintering pests seek entry.

💰 Professional Treatment Costs

Service TypeDIY CostProfessional Cost
Initial inspectionFree (self-inspect)$75–$150 (often credited to treatment)
One-time treatment$30–$100 in materials$150–$500
Annual service contractN/A$400–$900/year
Severe infestationOften ineffective alone$500–$2,500+

Prices vary by region, property size, and infestation severity.

❓ Common Questions About 🤢 Brown Marmorated Stink Bug (BMSB)

How do I confirm I actually have this pest (not something similar)?
The most reliable confirmation is a physical specimen — capture one and compare to reference images on this page. For cryptic pests (bed bugs, termites), look for secondary signs: frass, shed skins, mud tubes, or bites with a specific pattern. When uncertain, a professional inspection is faster than months of misidentification.
Can I treat this myself or do I need a professional?
DIY is effective for small, accessible infestations caught early. Professionals are worth the cost when: the infestation is inside wall voids or structural elements, multiple rooms are affected, you have health-risk pests (hantavirus, venomous species), or DIY has already failed twice.
How long until the infestation is completely gone?
Expect 3–8 weeks for most infestations with proper treatment. Insects with dormant life stages (pupae, eggs) extend the timeline because those stages are impervious to most insecticides. Follow-up treatments at 2 and 4 weeks catch each new cohort as they emerge.
What's the most common mistake people make treating this pest?
Treating only the visible pest population while ignoring the harborage site, entry point, or breeding location. Killing adults provides temporary relief but the population rebuilds from hidden egg cases, pupae, or new arrivals through unaddressed entry points.
📚 Sources: CDC Rodent Control · EPA Rodenticide Safety
Published: Jan 1, 2025 · Updated: Apr 7, 2026

🗺️ US Distribution — Brown Marmorated Stink Bug

image/svg+xml
Common Occasional Not Present
States Present
32
Occasional
6
Primary Region
Eastern United States
📊 Source: University extension services, USDA, CDC vector data, and published entomological surveys.