Indiana farmers have seen some very heavy rains this spring, and more is in the forecast for this week. This is leading to nitrogen loss in some areas. Denny Cobb, agronomist with Beck’s Hybrids, says flooded fields may have lost significant levels of nitrogen, “The flooded fields we had in parts of central and southern Indiana may have resulted in up to 5 lbs of nitrogen loss per day.” He added that the situation could have been worse if the temperature had been warmer, “The loss would have been worse with warmer weather; the fact that it was cooler really helped.”
Cobb recommends that growers evaluate the nitrogen loss while they are evaluating their stands, “I have been out with a few growers doing some pre-testing for side dressing nitrogen, and I have definitely seen some significant loss.” As part of the Practical Farm Research program, Becks has been trying some new technology that will evaluate nitrogen loss. Cobb said a unit called the Optics RX senses a plant’s needs and can adjust for the correct amount of nitrogen while on the go in a field.
Cobb says the cooler weather this spring has also prompted some herbicide crop injury. He said the cooler weather in May, along with the slow pace of early growth for the corn crop, has increased the incidence of injury. He added the many modes of action now being used by farmers can make it hard to identify this type of crop injury. He suggested using the University of Wisconsin’s Herbicide Mode of Action Key for Injury Symptoms, based on three traits of injury symptoms, which can be used to distinguish different herbicide modes of action.
1—If the plant absorbed the herbicide from the soil or if it was absorbed postemergence.
2—If the herbicide translocated to growing points (root tips or meristems) or if the herbicide had contact activity.
3—If the herbicide is selective for grasses or broadleaves or is nonselective.