UC IPM Online UC ANR home page UC IPM home page


SKIP navigation


How to Manage Pests

UC Pest Management Guidelines

Consperse stink bug adult.

Small Grains

Stink Bugs

Scientific name: Euschistus spp.

(Reviewed 2/07, updated 2/07)

In this Guideline:


Stink bugs are medium to large-sized bugs. Those that attack small grains are commonly grey brown to green in color and 0.38 to 0.5 inch long. Their bodies have a characteristic shield shape with a large triangle on the center back. They are most common where cereals are planted adjacent to rangeland near the foothills or desert.


Damage usually occurs when stink bugs feed in the head during milk or soft dough stage.


Observe fields frequently after heading, particularly those adjacent to desert or rangeland. If vegetation in areas surrounding the field is beginning to dry up, make more frequent observations. Using a sweep net, sample the margins, then move toward the center of the field; initially, stink bugs are generally confined to the edges of the field.

Management Decisions
No economic thresholds have been established for stink bug. No chemicals are currently registered for use against stink bug on barley, wheat, oats, or rye.


[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Small Grains
UC ANR Publication 3466
Insects and Mites
C. G. Summers, Entomology, UC Davis/Kearney Agricultural Center, Parlier
L. D. Godfrey, Entomology, UC Davis
Acknowledgment for contributions to Insects and Mites:
D. Gonzalez, Entomology, UC Riverside

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/r730300811.html revised: April 25, 2014. Contact webmaster.