The NPM Program and UW-Madison Dept. of Soil Science Professor Carrie Laboski have recently completed a new publication on Wisconsin’s two soil nitrate tests. Soil Nitrate Tests for Corn Production in Wisconsin: Preplant and Pre-Sidedress Nitrate Tests can be viewed and downloaded here.
Improving the efficiency of nitrogen (N) applications to corn is fundamental to promoting farm profitability and environmental quality in Wisconsin. By implementing the four Rs of nutrient stewardship — right rate, right time, right place, and right source — farms can tailor nutrient applications to maintain nutrient availability for crop growth while protecting water quality. Soil nitrate tests are examples of available tools to help determine the “right rate” of N for corn grain, corn silage, and sweet corn.
The amount of nitrogen available for crop uptake is influenced by many factors, so it is important to choose the proper soil nitrate test for your specific situation. Field specific considerations include: • Soil texture • Timing of manure and nitrogen fertilizer application • Previous growing season and overwinter precipitation • Previous crop and its nitrogen status
Guidance on how and when to use each of the tests along with advice on soil sample collection are found in this four-page publication. Printed copies will be available this summer.