Precision Agriculture: Maximizing Benefits with Better
March 14, 2007
Good cooks don't toss Worcestershire
sauce in the ice cream or mint in the mashed potatoes. Instead, they season
each dish with the best quantities and combinations of spices to enhance its
That's the concept behind precision agriculture, which is the practice of
modifying management techniques to meet within-field variations that affect
crop growth. Using an integrated approach, Agricultural Research Service (ARS) scientists in the Cropping Systems and
Water Quality Research Unit (CSWQ)
at Columbia, Mo., are determining which combinations of precision agriculture
methods work best.
Using data collected between 1991 and 2003, researchers
Sudduth determined that topsoil loss from field erosion significantly
reduced agricultural productivity. They also discovered that elevation and soil
electrical conductivity, which measures how easily soil allows an electrical
current to flow through it, were extremely helpful in identifying different
management zones. In fact, zone maps created with this information were more
accurate predictors of crop yield than maps made with traditional soil surveys.
In addition, the CSWQ team developed two site-specific management approaches
to help growers identify the fertilizer needs of specific areas within a field,
allowing for more accurate application. The first method assesses nitrogen
deficiency by measuring crop canopy reflectance. The second method, still in
development, relies on an automated soil sample collection and analysis system,
which could quickly and economically predict the soil's nitrogen-supplying
During the next five years, the researchers hope to show that their methods
decrease nutrient and sediment losses, increase profitability and improve soil
quality. Above all, they hope to demonstrate that precision agriculture can be
an economically viable tool for farmers.
more about the research in the March 2007 issue of Agricultural
ARS is the chief in-house scientific research agency of the
U.S. Department of Agriculture.