Traditionally in Ontario, soybeans have been grown without added fertilizer. Nitrogen is provided by fixation in the nodules of soybean roots, and phosphorus and potassium was only supplied if soil test levels were low. In recent years, yields have increased and crop rotations have shortened between soybean crops; this short interval is leading to nutrient deficiency symptoms being observed more often.
This project is designed to assess if fertilizer, in a variety of blends and placements, can increase soybean yields. The project is also evaluating what soil types would have the greatest responses based on the existing soil test levels.