Soil testing is going strong on harvested wheat fields right now. Many fields are being sampled before any fall tillage and getting the most consistent, best quality sample possible. The figure below shows the early trend in the amount of soil nitrate found in wheat fields in this region. Fall soil nitrate testing is a reflection of crop yield, applied N rate, N losses (volatilization, leaching, or denitrification), and N mineralized from the soil during the growing season.
Every season is unique. This year many areas were dry for all or part of the growing season. With dry conditions and a cooler than normal summer, the amount of N mineralized by soils this summer was probably less than normal. The data below is a first look at the trend in soil nitrate levels in wheat fields that have been tested so far. As you can see, as you go west, there are more fields testing over 100 lb/acre nitrate-N in the 0-24” soil profile. The areas with these high soil N levels were greatly affected by the 2017 drought. The only way to know what the soil nitrate level is in each wheat field is to soil test this fall. The best information comes from splitting fields into management zones based on productivity. Please call our technical support staff if you have any questions.