University of Missouri
Vol. 15, No. 6
Article 4 of 5
April 22, 2005
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Cutting of Corn Plants by Dingy Cutworm By Wayne Bailey |
Several reports of cutting of seedling corn plants by cutworm have been received from the Lexington area in the western part of the state and from the St. Charles area in eastern Missouri. The Dingy cutworm usually feeds on foliage and rarely cuts corn plants and causes economic loss. This spring the Dingy infestations are causing up to 5% cutting of emerging corn seedlings. This cutworm is gray in color and may show some faint reddish-brown coloration. A dull gray stripe can be found running the length of the back bordered by a narrow dark stripe on each side. Most larvae will be in the size range of 1-inch or more in length at this time in the season as they overwinter as large larvae and often cause damage 2-3 weeks prior to damage from black cutworm larvae. Insecticides are generally labeled for cutworm control in corn and not labeled by species. Thus those insecticides recommended for black cutworm also are labeled for control of dingy cutworm.
The risk of black cutworm infestations remains low at this time, although moth flights may occur throughout April to increase the risk from this pest on late planted corn. So far this spring numbers of black cutworm moths captured have remain low to moderate in number as compared to past years. No intensive captures have been reported so our predictive model for black cutworm damage has not been initiated. Problems with this pest are still possible, but the great amount of early planted corn along with low to moderate moth catches suggest that black cutworm problems in 2005 will be limited.
| INSECTICIDES LABELED FOR CUTWORM CONTROL IN FIELD CORN | |||
| Chemical | Trade Name | Rate/Acre | |
| Permethrin | *Ambush | 6.4 to 12.8 fl oz | |
| Permethrin | *Pounce 3.2EC | 4 to 8 fl oz | |
| Esfenvalerate | *Asana XL | 5.8 to 9.6 fl oz | |
| Cyfluthrin | *Baythroid 2 | 0.8 to 1.6 fl oz | |
| Bifenthrin | *Capture 2EC | 2.1 to 6.4 fl oz | |
| Bifenthrin | *Fanfare 2EC | 2.1 to 6.4 fl oz | |
| Chlorpyrifos | *Lorsban 4E | 1 to 2 pt | |
| Chlorpyrifos | *Nufos 4E | 1 to 2 pt | |
| Zeta-cypermethrin | *Mustang Max | 1.28 to 2.8 fl oz | |
| Gamma-cyhalothrin | *Proaxis | 1.92 to 3.2 fl oz | |
| Lambda-cyhalothrin | *Warrior | 1.92 to 3.2 fl oz | |
| Apply as postemergence rescue treatment when 2-4% or more of seedling corn plants are cut and larvae are present. Damage is more severe when plants are cut below ground as compared to cut above ground. * Designates a restricted use insecticide. Read and follow all label instructions | |||
Entomology
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