The sawfly caterpillar is a sporadic pest of wheat and barley, primarily on the Eastern Shore. It is easily distinguished from armyworms and other caterpillars by its solid-green body, its prominent amber head and its many legs (three pairs of jointed legs, each ending with a claw and eight pairs of short, fleshy prolegs without claws). Young caterpillars are lighter green and somewhat translucent. Mature worms are about 1.25 inches long and assume a curled position when disturbed.
Like armyworms, sawfly caterpillars must be detected when they are still young before head clipping occurs. Grain fields should be checked once each week starting the first week in May. This pest normally appears about a week earlier than armyworms, although mixed populations are frequently found in the same areas. First examine the crop for clipped heads and partially consumed leaf blades in rank growing areas and along field margins adjacent to woods. Shake the plants before counting the larvae on the ground. Unlike armyworms, this insect feeds during the day. If caterpillars are present, then sample as recommended for armyworms.
One sawfly caterpillar clips an average of five to eight grain heads during its larval development. The general rule is to treat when most caterpillars are greater than 0.75 inch long and worm counts exceed 0.4 per linear foot of row or 0.7 every square foot. The best time to treat is between May 15 and May 25. It is too late if the number of clipped heads per unit area is 3 to 4 times the average worm count and most caterpillars are greater than 1 inch long.
Fields with mixed infestations of armyworms and sawfly caterpillars may need treatment even if worm counts of each pest do not exceed threshold levels. Usually one foliar application of insecticide controls both insect pests. It is not wise to delay treatment in case armyworms appear later. If an armyworm problem is going to develop, the young worms are normally present when treatment is applied for sawfly caterpillars.
You are viewing records 1 - 4 of 4.| Insecticide and formulation | Rate of active ingredient per acre | Rate of formulation per acre | Time lmits: Days before harvest | Remarks |
|---|---|---|---|---|
| zeta-cypermethrin (Mustang MAX 0.8EC) |
0.02-0.025 lb | 3.2-4.0 oz | 14 | Restricted Use: Wheat and triticale. |
| lambdacyhalothrin (Lambda-Cy 1EC) |
0.025-0.03 lb | 3.2-3.84 oz | 30 | Restricted Use: Barley, oats, rye and wheat. |
| lambdacyhalothrin (Warrior II) |
0.025-0.03 lb | 1.60-1.92 oz | 30 | Restricted Use: Barley, oats, rye and wheat. |
| beta-cyfluthrin (Baythroid XL) |
0.014-0.019 lb | 1.8-2.4 oz | 30 | Restricted Use: Wheat only. |
