Last Year’s Drowned Out Corn, This Year’s Weed Problems

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

A number of fields last summer had poor stands of corn due to the wet soils. As a result, the weed control in those areas was very poor and the number of weed seeds in the soil is probably very high.

Be sure to scout those areas separately from the rest of the field to evaluate if additional weed control is needed or if the area needs to be treated the sooner to achieve good spray coverage.

  • Start clean, no weeds should be present at time of planting
  • Apply residual herbicides within 1 to 2 weeks of planting
  • Use full herbicide rates
  • Scout to be sure the residual herbicides were activated and evaluate if postemergence herbicides are needed
  • Treated emerged weeds while they are small and most susceptible (less than 4 inches tall)
  • Scout again to be sure treatments were effective and determine if a follow-up treatment is needed