Nutrient Management

We spend a great deal of time trying to establish the best nutrient management strategy. Many factors must be considered, such as yield, economics, environmental impacts, and application efficiencies. Our principle is to apply the most economical rate of fertilizer and minimize environmental impacts. For nutrients such as phosphorus and potassium, we test our soils regularly using a zone sampling approach. We then apply these nutrients on a variable rate basis, incorporating the nutrients into the soil using our Soil Warrior strip-till machine. These practices allow us to achieve our goal of minimizing losses to the environment and maximizing economic returns. This approach doesn't necessarily provide maximum yields, however.

We have been variable rate applying nitrogen since 2003. We started by sidedressing anhydrous ammonia based on a Pre-Sidedress Nitrate Test (PSNT) in different zones across the field. These zones were most often created by an Electromagnetic Induction (EMI) machine but we also used yield maps, soil colour from satellite imagery, and topography maps.

In 2013, we purchased a Y-drop application system and mounted it on our Spra-Coupe 7650 high clearance sprayer.  This allows us to use our sprayer more efficiently and we are also able to apply 28% UAN to corn later in the season. Recent research has shown that corn takes up a large proportion of its nitrogen needs after tasseling.

In 2015, we added an AgLeader OptRx system to the sprayer so we can variable-rate apply our nitrogen based on the nitrogen status of the corn crop. When the corn is 4-5’ tall we will use the OptRx to read the corn crop, derive a Normalized Difference Red Edge (NDRE) value, then apply a rate of nitrogen that corresponds to the NDRE. Thus, where the corn is healthy and has an ample supply of nitrogen, the NDRE value is higher and we apply a lower rate of nitrogen. Conversely, where the corn isn't performing as well due to lack of nitrogen, the NDRE is lower and we apply a higher nitrogen rate. By doing so we improve our economic returns and minimize our environmental impacts.

We are beginning to look at organic sources of nutrients such as animal manures, municipal sewage products, and compost. These products can improve our soils not only with the broad spectrum of nutrients they supply, but also with the organic matter, bacteria, and fungi that come along with it.  We can use these products to supplement, and maybe someday replace, our commercial fertilizer products.