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Corn Rootworm Larvae Reference Page

Common and scientific names:  Western Corn Rootworm (Diabrotica spp.)

Pest description and crop damage: Larvae are 0.5 inch long, pale yellow, with brown-yellow heads. They feed on corn roots and cause stunting, lodging, and occasionally death of plants.

Management—cultural control: Crop rotation is an important method of control. Avoid planting corn following corn. See University of Idaho publication CIS 924 for more details.

 Management—chemical control

1.   Furadan 4 F at 0.075 lb ai/1,000 row ft. PHI 30 days. Apply at planting as band over the row or by side-dressing. May be applied as basal spray postemergence.

2.   Phorate or Thimet 20 G at 1.2 oz ai/1,000 row ft. Use at planting time. Do not place granules in direct contact with seed

3.   Counter 20 CR at 1.2 oz ai/1,000 row ft. May be side-dressed at cultivation time if preplant treatment was not made. To be effective, apply before corn is 12 inches high.

4.   Lorsban 4 E at 3 lb ai/a (preplant). Do not graze livestock or feed silage to meat or dairy stock for 14 days or fodder for 35 days. Apply high rate preplant or at cultivation. Apply at cultivation at base of plants on both sides of row just ahead of cultivator shovels and cover with soil around brace roots. Re-treat as necessary, but do not exceed 15 pt/a.

5.   Lorsban 15 G at 0.075 lb ai/1,000 row ft. Apply at planting as a band or at cultivation as a band or side-dress.

6.   Mocap 6 E at 0.067 to 0.11 lb ai/1,000 row ft. Band on row over closed seed furrow.

7.   Mocap 10 G at 1.2 oz ai/1,000 row ft. Band on row over closed seed furrow.

8.   Force 3 G at 4 to 5 oz product/1,000 row ft. T-band or in-furrow at planting.

9.   Fortress 5 G at 3 oz product/1,000 row ft. T-band or in-furrow only at planting. Must be applied with smartbox system.

 Source: 2002 PNW Insect Management Handbook

Colorado State University Western Corn Rootworm Fact Sheet

Images of Corn Rootworm

June 25, 2002-jn