By Reagen Tibbs
Illinois grain producers face a series of difficult and complex decisions each growing season. All these decisions can have a major impact on yields and overall profitability of the operation. These decisions can range from what variety to plant, when to plant, and what inputs to apply during the growing season. Farmers can use many different sources of information, such as soil tests and gained knowledge, to determine if fertilizers need to be applied and when they should be applied. While these help to paint the picture for a producer, the crop itself is the best source to determine how much fertilizer is being used and if more is needed. Three recent research studies explore how corn plants at various stages during the growing season can be used to guide fertilizer decisions for the current and future growing seasons. This post will examine these studies and highlight the practical findings that producers can consider when they are setting their fertilizer strategy for the next growing season.
Early-Season Evaluation
Nitrogen is perhaps the most important macronutrient that influences corn growth and yield, so much so that it is the primary focus of fertilizer applications for corn producers. However, in-field variation in soil type, topography, and rainfall means that nitrogen availability can differ greatly across a field. Furthermore, losses due to leaching and denitrification makes the decision of when and how much nitrogen to apply more complicated. Having enough nitrogen at the right time for a plant to use it is extremely difficult to figure out. While methods such as soil tests and leaf tissue sampling help determine available nitrogen, there are still gaps in the information they provide.
Source : illinois.edu