Small grain-Cereal leaf beetle

Oulema melanopus

Pest description and crop damage Adults are small beetles about 0.25 to 0.375 inch, with a metallic-blue head and wing covers, red pronotum, and yellow-orange legs. Larvae are yellow to yellow-brown with a dark mass of slimy fecal material on their backs.

Both adults and larvae feed on leaves. Feeding causes a characteristic stripping of the leaves.

Sampling and thresholds Treat when there are three larvae or eggs per plant up to the boot stage. After boot, treat at one larva per flag leaf.

Management-biological control

These insects are controlled easily by introduced parasitoids. The primary biocontrol agents (parasitoids) are two wasp species; Tetrastichus julis (a larval parasitoid) and Anaphes flavipes (an egg parasitoid).

Management-chemical control

Foliar sprays

  • alpha-cypermethrin (Fastac EC) at 0.012 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.
  • Beauveria bassiana GHA (Mycotrol ESO) at 0.5 to 2 pints/a. PHI 0 days. Do not apply more than 6 pints/a. Some formulations are OMRI-listed for organic use.
  • beta-cyfluthrin (Baythroid XL) at 0.008 to 0.014 lb ai/a. PHI 30 days. REI 12 hr. Do not forage or graze within 3 days of application. Retreatment interval 3 days. Do not exceed 0.038 lb ai/a per season
  • chlorpyrifos (Lorsban Advanced) at 0.47 lb ai/a. PHI 14 days forage and hay; 28 days grain and straw. REI 24 hr. Do not exceed 2 treatments per acre per year. Wheat only.
  • chlorpyrifos/gamma-cyhalothrin (Cobalt) at 0.3 to 0.58 lb ai/a. REI 24 hr. PHI 14 days forage and hay, 30 days grain and straw. Not more than 2 applications per year. Do not exceed 1 lb ai/a chlorpyrifos per season. Wheat only.
  • 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.
  • cyfluthrin (Tombstone) at 0.016 to 0.028 lb ai/a (wheat only). PHI 30 days. Pre-grazing or foraging interval 3 days. REI 12 hr. Retreatment interval 3 days. Do not exceed 0.076 lb ai/a per season.
  • diflubenzuron (Dimilin 2L) at 0.0625 lb ai/a. PHI for grain and straw 50 days; forage 3 days; hay 15 days. REI 12 hr. One treatment per season.
  • gamma-cyhalothrin (Declare) at 0.01 to 0.015 lb ai/a. PHI 30 days. REI 24 hr. Do not apply more than 0.03 lb ai/a per season. Do not graze or forage within 7 days of application. Do not feed straw within 30 days.
  • lambda-cyhalothrin (Silencer, Warrior II) at 0.02 to 0.03 lb ai/a. PHI 30 days. REI 24 hr. Do not graze or forage within 7 days of application. Do not feed straw within 30 days of last treatment. Do not exceed 0.06 lb ai/a per season.
  • lambda-cyhalothrin/tebuconazole (Crossover) at 0.14 lb ai/a. PHI 30 days. REI 24 hr. Do not exceed 0.11 lb ai/a tebuconazole or 0.06 lb ai/a lambda cyhalothrin per season. Feeding restrictions apply. Do not exceed 8 fl oz/a or 0.139 lb ai/a per season.
  • lambda-cyhalothrin/chlorantraniliprole (Besiege) at 0.059 to 0.098 lb ai/a. PHI 30 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.06 lb ai lambda-cyhalothrin or 0.2 lb ai chlorantraniliprole per year. Feeding restrictions.
  • lambda-cyhalothrin/thiamethoxam (Endigo ZC) at 0.055 to 0.07 lb ai/a. PHI 30 days. REI 24 hr. Retreatment interval 7 days. Do not exceed 0.06 lb ai/a lambda-cyhalothrin or 0.125 lb ai/a thiamethoxam per season. Barley only.
  • methomyl (Lannate SP) at 0.225 to 0.45 lb ai/a. PHI 7 days. REI 48 hr. Do not exceed 1.8 lb ai/a per season. Do not exceed 4 applications per season. Wheat only.
  • 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.
  • spinetoram (Radiant SC) at 0.0156 to 0.047 lb ai/a. PHI 21 day of grain or straw harvest; 3 days of forage, fodder or hay harvest. REI 4 hr. Do not exceed 0.141 lb ai/a per year. Limit 3 applications per year. Retreatment interval 4 days.
  • spinosad (Success, Entrust SC) at 0.031 to 0.094 lb ai/a. PHI 21 days for grain and straw; 3 days for forage, fodder or hay. REI 4 hr. Do not exceed 0.28 lb ai/a per year. Limit 3 treatments per year. Entrust SC is OMRI-listed for organic use.
  • zeta-cypermethrin (Mustang) at 0.022 to 0.05 lb ai/a. 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 0.12 to 0.28 lb ai/a. PHI 14 days for forage or hay; 28 days for grain and straw. 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 chlorpyrfos per season. Wheat only.