| Black cutworm |
- No-till
- Winter annual weeds (particularly common chickweed present within 10 days of planting)
- Nearby alfalfa field (particularly a new seeding)
- River bottom land or fields with wet weedy areas
|
| Stalk borer |
- Corn planted in old alfalfa field with clumps of orchardgrass present
- Corn bordered by clump grasses like orchardgrass
- Corn planted into a rye mulch
|
| Armyworm (True) |
- Corn planted into a rye mulch
- Corn planted into small grain
- Corn planted into grass sod
- Corn field edges adjacent to small grain or rye mulch
|
| Slugs |
- No-till
- Heavy manure applications
- Dense stands of weeds
- Bordered by timber
|
| Seed corn maggot |
- Heavy manure applications
- Soils high in organic matter
- Damp and cool soil conditions
- Planting immediately or within 1–2 weeds into tilled, green vegetation
|
| Wireworm |
- Corn planted in a field that was in grass sod within the last three years
- Silt-loam soils
|
| White grub |
- Corn planted in a field that was in grass sod within the last two years
|
| Billbug |
|
| Corn rootworm larvae |
- Second year or more of corn
- Green silk corn present when adults were active the previous year
- Soils with high clay content
- Moderate soil moisture conditions from August to June
|
European corn borer
(1st generation) |
- Earliest planted corn fields in the area
- Corn over 24 inches tall when moths are present
- High plant densities and closed rows
|
European corn borer
(2nd generation) |
- Latest planted corn fields in the area
- Corn plants silking (green silk) when moths are flying
- High plant densities
|
