Farmers would like nothing better than to control Mother Nature. Unfortunately, even in cases where extensive nutrient management and conservation plans are in place, excessive rain can lead to soil and nutrient losses. The effects of last year’s extreme drought in the Midwest, followed by this year’s persistent and excessive rainfall, provide a very clear reminder of an important and unfortunate fact: uncontrollable weather at the wrong time can wipe out the water quality benefits of even the best farm nutrient management programs.
When last year’s crops failed to grow or mature due to the drought, nutrients that would normally have been utilized in the formation of grain went unused. These underutilized nutrients were then susceptible to loss. Farmers and agronomists in the Upper Midwest worked diligently to meet the challenge posed by nutrients’ potential to reach local surface waters and be transported to the Gulf of Mexico by flooding events. This spring’s record rainfall, taking place before crops were actively growing, likely washed many of the leftover nutrients out of farm fields despite the best efforts of farmers and ag retailers.Farmers and agricultural retailers launched the N-WATCH soil nitrate testing program in the Upper Mississippi River Basin on many fields in Illinois and Iowa to assess the remaining nutrients in the soil and track their movement in the soil profile. With N-WATCH, farmers were able to assess levels of nitrogen remaining in their corn fields and use this information for the 2013 growing season.
Last fall many farmers adopted additional and aggressive measures to hold the drought-induced unused nutrients in their fields. These measures included more extensive soil testing programs such as N-WATCH, the use of precision application technologies, and planting cover crops to absorb some of the in-field nutrients and prevent erosion. But even with these and other important nutrient management programs in place, there was no effective way to stop unused nutrients from being lost in heavy spring rains before crops were planted or growing.
Going forward, with the support of the Natural Resources Conservation Service and local and state agencies, new programs like N-WATCH are positioned to expand to cover more acres. Over time, this should result in improved water quality.
Good crop nutrient management is important for many reasons. One of these is to meet the worldwide challenge to double food production to feed the growing world population by 2050. Research shows that without nitrogen fertilizer farming would support only about half of the current human population. Another reason for good nutrient management is, of course, to protect water quality.