Amphitornus, Melanopus, and Xanthippus spp.
Pest description and crop damage Nymph and adult grasshoppers can be a problem at seedling emergence. During years of high populations, grasshoppers migrate into emerging stands and devour the cotyledons. Damage is usually limited to the field margins, but total stand loss there can occur. An economic threshold of 7 to 12 grasshoppers per square meter is recommended.
Management-Chemical control (Foliar Treatment)
- azadirachtin (AzaGuard) Spray 10 to 16 oz when pests first appear. Repeat application every 7 to 10 days. Use in combination with 0.25 to 1.0% non-phytotoxic crop oil in sufficient water to cover undersides of leaves. Some formulations are OMRI-listed for organic use.
- Beauveria bassiana GHA (Mycotrol O) at 0.25 to 2 quart/a. Apply in sufficient water to thoroughly cover foliage infested with insects, typically 5 to 100 gal of water per acre. REI 4 hr. Mycotrol ESO contains live spores of the naturally occurring fungus, Beauveria bassiana Strain GHA. Spores are alive and may be harmed by storage at high temperatures or contact with water for more than 24 hours. OMRI-listed for organic use.
- bifenthrin (Bifen 2 AG Gold, others) at 0.033 to 0.04 lb ai/a or 2.1 to 2.6 fl oz/a. Do not exceed 0.08 lb ai/a or 5.12 fl oz per acre per season. Repeat applications if needed to maintain control, but do not apply less than 14 days apart.
- chlorantraniliprole (Besiege, others) at 5.0 to 10.0 fl oz/a. Do not exceed a total of 28.0 fl oz of Besiege or 0.09 lb ai of lambda-cyhalothrin-containing products or 0.2 lb ai of chlorantraniliprole-containing products per acre per year. PHI 21 days. Minimum interval between applications is 5 days. If adjuvants are used, use only a non-ionic surfactant (NIS).
- deltamethrin (Delta Gold) at 0.009 lb ai/a. Do not apply more than 1.5 fl oz of Delta Gold per acre on canola in one growing season. Do not apply within 7 days of harvest.
- gamma-cyhalothrin (Declare) at 0.0075 to 0.015 lb ai/a. PHI 7 days. Do not apply more than 0.045 lb ai per acre per season.
- lambda-cyhalothrin (Lamda-Cy AG) at 0.015 to 0.03 lb ai/a. PHI 7 days. Do not apply more than 0.09 lb ai (0.72 pt or 11.52 fl oz of product) per acre per year. Do not apply within 7 days of harvest.
- zeta-cypermethrin (Mustang Maxx) at 4.0 fl oz/a (0.025 lb ai/a). PHI 7 days. Do not apply more than 24 fl oz of product (0.15 lb ai) per acre per season. Do not make applications less than 7 days apart.
Management-chemical control (Seed Treatment)
- imidacloprid (Gaucho 600) at 10.24 to 25.6 fl oz per hundredweight of seed. In areas where foliar insects are in high numbers, the higher application rate is recommended. Do not graze for feed.