Labops hesperius and other Labops spp.
Irbisia pacifica and other Irbisia spp.
Pest description and crop damage The black grass bug is a grayish-black insect approximately 0.25 inch long, with silvery scales, and somewhat pear-shaped body. Adults have prominent compound eyes and may have shortened or absent wings. This pest feeds on a wide variety of grasses, including wheatgrass, brome grass, orchardgrass, and bluegrass. In field crops some of the crops it targets are barley, wheat, rye, and oats. Great Basin wildrye and wheatgrasses such as bluebunch wheatgrass, crested wheatgrass, and intermediate wheatgrass are particularly susceptible. Feeding causes pale spots on the leaves of cereals and, in severe infestation, a general yellowish, stippled appearance. This leads to decreased forage quality and reduced growth.
Management-chemical control
- bifenthrin (Brigade 2EC, Discipline 2EC) at 0.05 to 0.1 ai/A. PHI 30 days for forage and grass. Do not apply more than 0.2 lb ai/A per year. REI 12 hr. Retreatment interval: 14 days.
- carbaryl (Sevin 4F) at 0.5 to 1 lb ai/A. PHI 14 days. REI 12 hr. Limit two treatments per year. Retreatment interval 14 days. Do not exceed 3 lb ai/A per year. (See various labels under "Rangeland").
- chlorantraniliprole/lambda-cyhalothrin (Besiege, Voliam Xpress) at 0.0391 to 0.0652 lb ai/A for chlorantraniliprole and 0.0195 to 0.0325 lb ai/A for lambda-cyhalothrin. PHI 0 days for grazing or cut for forage; 7 days for cut grass to be dried and harvested for hay. Retreatment interval 7 days. REI 24 hr. Do not exceed 0.09 lb ai/A lambda-cyhalothrin or 0.2 lb ai/A chlorantraniliprole.
- gamma-cyhalothrin (Declare) at 0.01 to 0.015 lb ai/A. PHI 0 days for grazing or cut for forage; 7 days for cut grass to be dried and harvested. REI 24 hr. Do not exceed 0.045 lb ai/A per season.
- lambda cyhalothrin (Warrior II) at 0.02 to 0.03 lb ai/A. PHI 0 days for grazing and forage; 7 days to be dried for hay. REI 24 hr. Do not exceed 0.03 lb ai/A per cutting or 0.09 lb ai/A per season. Retreatment interval 30 days.
- zeta-cypermethrin (Mustang, Mustang Maxx)-Mustang at 0.035 to 0.05 lb ai/A; Mustang Maxx at 0.0175 to 0.025 lb ai/A. PHI 3 days for cutting and grazing; 7 days for seed. REI 12 hr. Do not apply more than 0.05 lb ai per cutting or 0.15 lb ai per season of Mustang or 0.025 lb ai per cutting and 0.075 lb ai per season of Mustang Maxx. Retreatment interval 7 days.