Cutworms are the larvae of moths. These night-flying moths are frequently attracted to lights at night. The 1-1/2 to 2-inch moths are dull-gray to brown with yellow, gray, light brown, and black designs on the front wings. The hind wings are usually solid in color and lighter than the front wings. Moths lay eggs singly or in clusters on the leaves of grasses, weeds, other host plants, and sometimes on the bare ground.
Cutworms are smooth-skinned and somewhat shiny. They range in color from gray to dark brown with distinctive stripes and spots. When fully grown, cutworms can reach 1-3/4 inches in length. Cutworms commonly coil up in a "c" shape when disturbed.
Cutworms feed mostly at night and hide during the day under clods of soil or in burrows below the soil surface. They cut off the stalks of young plants at or just below the soil surface and feed on the buds or leaves. They rarely consume the entire plant, but more commonly move to the next plant in the row or to another row. Infestations typically are not uniform within a field, so the loss of a plant stand tends to occur only in parts of a field.
Late planting, moderate to heavy infestations of broadleaf weeds prior to planting, poor field drainage, or an abundance of crop residue, especially soybean straw, are factors that contribute to cutworm problems. Fields with combinations of these characteristics or a history of cutworm problems have an increased potential for damage. Preplant or planting time applications of soil insecticides or broadcast sprays may reduce cutworm damage but are generally not an economical strategy. Fields receiving a preventive cutworm treatment should be watched; economic damage may occur where cutworm pressure is great. Rescue treatments can be applied when field inspection indicates that an economic infestation is present. This is the most cost efficient strategy to follow. Frequent field scouting and early detection of the problem is essential. Treat when 3 % of the stand is cut and 2 or more larvae (1" or smaller) are found per 100 plants. Control may be unsatisfactory if the soil is dry and crusted and the cutworms are feeding well below the soil surface. Under hot, dry conditions, control with some products may be enhanced by cultivation or use of rotary hoe after application.
Insecticide | Rate | Notes |
Ambush2 E | 6.4 - 12.8 fl oz per acre | Apply no more than 5 days prior to emergence. |
Asana XL | 5.8 to 9.6 fl oz per acre | |
Aztec 2.1% G | 6.7 oz per 1,000' of row | Apply as a T-band |
Aztec 4.67% G | 3 oz per 1,000' of row | Apply as a T-band |
Baythroid 2 | 0.8 to 1.6 fl oz | grain/fodder 21 days, green 0 day |
Capture 2 EC | 0.3 oz per 1,000' of row | Apply as a T-band |
Capture 1.15G | 6.4 to 8 oz per 1,000' of row | Apply as a T-band |
Capture 1.15G | 3.2 to 8 oz per 1,000' of row | Apply in-furrow |
Force 3% G | 4 to 5 oz per 1,000' of row | May use 3 to 4 oz with T-band or banded applications in 1st year corn only |
Lorsban 15% G | 8 oz per 1,000' of row | Apply as a T-band or band |
Lorsban 4 E | 2 to 4 pints per acre | Preplant incorporation |
Lorsban 4 E | 2.4 fl oz per 1,000' of row | Apply as a T-band in front of press wheel |
Pounce 1.5% G | 8 oz per 1,000' of row | Apply as a T-band or band |
Pounce 3.2 EC | 4 to 8 fl oz per acre | Broadcast or banded sprays |
Warrior T | 1.92 to 3.20 fl oz per acre |
Insecticide | Rate per Acre | Notes |
Ambush 2 E | 6.4 - 12.8 fl oz per acre | |
Asana XL | 5.8 to 9.6 fl oz per acre | 21 day PHI |
Baythroid 2 | 0.8 to 1.6 fl oz | grain/fodder 21 days, green 0 day |
Capture 2 EC | 2.1 to 6.4 fl oz | 30 day PHI |
Lorsban 4 E | 1 to 2 pints | 35 day fodder interval |
Mustang 1.5 | 1.4 to 3.0 fl oz | 30 day grain, 60 day silage PHI |
Penncap-M 2FM | 4 pints | Ground only, 12 day PHI |
Pounce 3.2 EC | 4 to 8 fl oz | 30 day PHI |
Sevin 80 S | 2-1/2 lbs | 12" band |
Warrior T | 1.92 to 3.20 fl oz per acre | 21 day harvest |