Small grain-Barley thrips

Limothrips denticornis

Pest description and crop damage Black, yellowish, or reddish, winged or wingless, small insects about 0.0625 inch long that cause foliage to turn whitish or rusty. When abundant, they may injure flowers and reduce yields.

Management-chemical control

  • alpha-cypermethrin (Fastac EC) at 0.02 to 0.025 lb ai/a. PHI 14 days. REI 12 hr. Retreatment interval 14 days. Do not exceed 0.075 lb ai/a per season. Wheat and triticale.
  • azadirachtin (Aza-Direct, Ecozin 3EC) at 0.43 lb ai/a. PHI 1 day. REI 4 hr. Retreatment interval 7 days. Some formulations are OMRI-listed for organic use.
  • Chromobacterium subtsugae (Grandevo) at 0.6 to 0.9 lb ai/a per 100 gal. PHI 0 days. REI 4 hr. OMRI-listed for organic use.
  • pyrethrin-There are several pesticides containing various amounts of pyrethrins. Check each label for the use and amount needed. Some formulations are OMRI-listed for organic use.
  • zeta-cypermethrin (Mustang) at 0.04 to 0.05 lb ai/a (wheat and triticale only). 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. Barley, wheat and triticale only.
  • zeta-cypermethrin/chlorpyrifos (Stallion) at 0.22 to 0.28 lb ai/a. PHI for forage or hay 14 days; grain and straw 28 days. REI 24 hr. Retreatment interval 14 days. Do not allow meat or dairy animals to graze within 28 days of application. Do not exceed 0.05 lb ai/a zeta-cypermethrin or 0.5 lb ai/a chlorpyrifos per season. Wheat only.