Nitrogen losses from fall manure application need to be quantified, to improve management techniques, says a Guelph researcher.

Prof. John Lauzon, Department of Land Resource Science, is working to ensure the numbers used in nutrient-management plans to calculate nitrogen levels meet current environmental standards.

"In the past, research focused on the agronomic value of nutrients in manure and did not specifically measure loss," he says. "This study will focus on nitrogen losses from manure in the fall and nitrogen availability in the spring. If the fall losses are found to be too large, it may mean that manure application volumes will be restricted."

Under the nutrient management act, the nitrogen index (which is used to calculate the potential for nitrogen loss), is based on uptake of nitrogen in the crop, compared to the removal of nitrogen by the crop. It also factors in the soil characteristics which may lead to loss of nitrogen, other sources of loss such as runoff and leaching.

So at the Elora and Woodstock research stations -- both of which are fairly intensive livestock areas – Lauzon will study the losses of manure applied at two different application rates in the late summer and late fall, compared with early spring. Beef, liquid dairy, poultry and hog manure will be examined for nitrogen losses during each application time and rate.

Nitrogen losses will be determined through soil sampling while the agronomic benefit of the manure application will be evaluated on the basis of both crop yield and crop nitrogen uptake.

Other researchers working on the project include Profs. Bill Dean, Department of Plant Agriculture, Gary Parkin, Department of Land Resource Science, and Ivan O’Halloran, Ridgetown College.

Sponsors for this component of the study include the Agricultural Adaptation Council, Ontario Cattlemen’s Association, the Ontario Corn Producers Association, Ontario Ministry of Agriculture and Food, Ontario Pork and the Poultry Industry Council.