Variable rate technology has been around for a number of years, but has gained popularity with advances in technology. While it was once used mainly for lime application to even out variability in pH levels in a field, today it is used for fertilizer application, chemical application and for planting population as well.
Variable rate fertilizer application has become one of the most important uses of variable rate technology. It targets fertilizer application to high yielding areas of a field and away from lower yielding areas of a field. This can increase fertilizer use efficiency and decrease fertilizer losses to the environment. Studies have shown that using VRT fertilizer application can reduce nutrient losses from 10-30%.
A pilot program in the Chesapeake Bay watershed utilizing variable rate technology is looking to assess the effectiveness of VRT technology in reducing nutrient losses which ultimately end up in Chesapeake Bay. Ultimately they hope to develop programs to increase adoption of the technology.
The following is an example of a variable rate fertilizer application map:
The rates in the bottom left-hand corner are in pounds per acre. The darkest green areas get the highest rates, the gray areas get a zero rate, with varying rates between.
Continued adaptation of variable rate technology would mean increased benefits to the environment, particularly large watersheds. Even though much attention has been paid to the Chesapeake Bay watershed, other watersheds such as the Mississippi River watershed will start to get more scrutiny. We in agriculture need to do our part in protecting the environment through whatever means is available to us, and show our consumer customers that we understand the importance of environmental responsibility.