Nutrient Management Behavior on Wisconsin Dairy Farms

Nutrient management plans for livestock operations should account for rates and timing of manure application to cropland, as well as how manure is integrated with other nutrient sources. Little is known, however, about actual nutrient management behavior of farmers, and what changes may be needed for farmers to adhere to nutrient management regulations. Detailed records were kept on fertilizer, manure, and legume N and P applications on 33 representative Wisconsin dairy farms during the period October 2003 through September 2004. Average available N applications ranged from 118 to 200 kg ha-1 of which 40% was derived from fertilizer, 30% from manure and 30% from previous legume. On a regional basis, the following percentages of corn (Zea mays L.) area fell within available N application categories of 0, 1 to 80, 81 to 160, 161 to 240 and >240 kg ha-1, respectively: in the Northeast (NE) region,