Small grain-Grass bug


Black grass bug (Labops hesperius)
Pacific grass bug (Irbisia pacifica)

Pest description and crop damage Bug is grayish black, about 0.25 inch long, and somewhat pear-shape. Feeding causes pale spots on the leaves of cereals and, when severe, gives leaves a general yellowish, stippled appearance.

Infestations of this insect occasionally occur in volunteer grain or grain growing under poor soil or moisture conditions. It has not been a common problem in grain-growing areas. For more information about black grass bugs, look at University of Idaho CIS 1128 publication, available online:

Management-chemical control

Foliar sprays

  • zeta-cypermethrin (Mustang) at 0.022 to 0.05 lb ai/a (wheat and barley). PHI 14 days - also for forage and hay. REI 12 hr. Retreatment interval 14 days. Do not apply more than 0.25 lb ai/a per year.