With early harvest, warmer weather growers reminded of manure application BMPs
Minnesota’s corn farmers continue to be on pace to wrap up their corn harvest earlier than usual, according to the latest USDA data.
One-fifth of the state’s corn crop has been harvested as of Oct. 3, a 65% increase from the same point in 2020 and a 2,000% increase from the same point in 2019.
The earlier harvest has corresponded with the corn crop reaching maturity faster than usual. According to USDA data, 90% of the state’s corn crop has reached maturity. Between 2016 and 2020, 73% of the crop had reached maturity, on average, by Oct. 3.
Drought conditions statewide significantly affected crop conditions this season with just 36% of the state’s corn crop in good or excellent condition, compared to 71% at the same point in 2020.
Given the early harvest and warmer weather, growers are reminded of the changes to the National Pollutant Discharge Elimination System (NPDES) general permit and related manure application requirements. In 2020, MPCA proposed changes to the general permit through a public input process. The Legislature did approve minor changes to the permit, but the Environmental Protection Agency (EPA) disapproved of those changes in late August purely on a question of process. The EPA offered no comment on the merit of the changes proposed by the Legislature.
For application from Oct. 1 to Oct. 15, one of the four nitrogen best management practices must be implemented:
- the soil temperature is below 50 degrees at the start of manure application;
- a nitrogen stabilizing agent/product is added at the recommended inclusion rates;
- a cover crop is established in accordance with the requirements for September manure applications; or
- a split application of nitrogen where no more than one-half of the recommended nitrogen rate is applied before Oct. 15. Winter application of the remaining recommended nitrogen rate is prohibited.
More information on the notable changes from the previous NPDES permit can be found here.
