Traditional soil nitrogen tests do not account for all the nitrogen found in the soil that is available to plants, resulting in the potential for over application of nitrogen fertilizer by agricultural producers. This over application increases nitrogen transport to Texas rivers and lakes, which can accelerate eutrophication and substantially increase water treatment costs. In addition, the application of excessive nitrogen fertilizer increases producers' costs and reduces their profitability.
This project will demonstrate an innovative soil test methodology, which uses soil microbial activity to account for all sources of plant-available nitrogen in the soil. Since the majority of soil nutrients are cycled through the soil microbial biomass, testing soil microbial activity provides an excellent snapshot of the soil health prior to fertilizer application. The project will demonstrate the potential for reduced nitrogen runoff due to reduced nitrogen application based on this soil test methodology. Project members will establish demonstration sites at USDA's Agricultural Research Service facilities at Temple and Riesel and on private land. Crop yield, economic throughput, fertilizer cost, and water quality data will be presented at local and national producer and scientific meetings.
The results of this project have the potential to revolutionize soil testing procedures and resulting fertilizer recommendations. Basing fertilizer application rates on soil tests that more accurately account for the total amount of plant-available nitrogen in the soil could have tremendous socio-economic and environmental benefits. The environment will benefit as less nitrogen is introduced into streams and rivers. Similarly, cost savings for produces should result in increased profitability.