Limiting Nutrient Leaks N By Dr. Tom Bruulsema, CCA atural ecosystems are Best management practices Going further in limiting often nutrient-limited. limit the leaks. Applying the leaks requires further research They support flora and fauna right source at the right rate, and technology. Current adapted to specific nutrient time and place ensures that technologies include limitations. With a diversity crops take up the largest inhibitors and coatings that of species competing for a possible portion, limiting the control release. Future limited supply of nutrients, amount available to be technologies may include little leaks out of the system. leaked. nutrient-need forecasts related to weather. All Cropping systems are technologies require on-farm testing to validate their different Best management Agricultural management effectiveness. practices are specific to adds nutrients to boost the soil and cropping productivity. While higher system They often include: Are some crops leakier yields save land for natural • Soil and plant analysis. than others? ecosystems, nutrient leaks can Some consider corn to be perturb them by altering their • Placement for maximum particularly so, and worry that species composition. plant availability. the biofuel-demand-driven Nitrogen is a nutrient that • Nutrient budgeting to increase in corn production leaks in many ways. It can match crop removal. will lead to larger leaks. leach away as nitrate, causing However, nutrient leaks can • Mapping and managing issues for water immediately occur before, during and after soil variability among and below the field and as far the growth period of any within fields. away as the ocean. It can leak particular crop. It is important • Timing applications and to the air in the form of to consider the management controlling release to nitrous oxide, depleting the of the full crop rotation. synchronize with plant ozone layer in the Extensive research in the demand. stratosphere and warming the Chesapeake Bay watershed climate through the • Selecting genetics and has shown that cover crops greenhouse effect. Or it can managing for higher yield following corn is one way of leak to the air as ammonia, and nutrient uptake. reducing nitrate leaks. possibly affecting air quality • Maintaining a buffer zone Increasing global demand and smog, and potentially between the fertilized field for food, fiber and fuel disturbing nearby natural and watercourses. increases expectations for ecosystems. • Growing cover crops to crop productivity. Best The nutrient phosphorus retain nutrients for the next management of both cropping leaks in small amounts. But growing season. systems and nutrients gives even the small concentrations • Conservation tillage to the best chance of preserving in surface runoff or tile drain minimize runoff and natural ecosystems, and water can stimulate blooms of erosion. limiting the nutrient leaks that algae in rivers and lakes. might affect them. Tom Bruulsema is a Certified Crop Adviser employed by the International Plant Nutrition Institute as their Northeast Director located in Guelph. There are over 500 Certified Crop Advisers (CCA) in Ontario. Each CCA has demonstrated their knowledge about Ontario crop production by passing the required exams. In addition, they have the crop advisory experience, the education, the commitment to continuing education and have signed a comprehensive code of ethics, which places the grower’s interests first. This industry driven program helps ensure that Ontario crop producers are well served by those providing their crop production advice. This article was written by one of those CCA’s.