Once in the plant, the fungi do not grow much until the plant is stressed. This process happens every year, but the later in the season it happens, the better off the crop is. Some falls the stalks are still green and full of moisture at harvest, an indication that the plant has not had much stress, and the fungi population has not grown to invade the stalk. Rainfall and high humidity conditions like fog at night accentuate the problem. Many of these fungi need water to grow.
Proper stalk rot management varies from field to field.
To minimize stalk rot loses, scout fields around 40 days after pollination and look for soft stalks. Fields with more that 15 percent rotted stalks should be harvested as early as possible. Management that minimizes stress to the plant, such as crop rotation, can be helpful. Rotation to non-host crops prevents buildup of stalk rotting fungi. High plant populations favor stalk rot by increasing competition for light, water and nutrients.