Satellites and Planes Scan Cornfields for Clues

For the past three years, an airplane has been flying over a U.S. Department of Agriculture research center in Beltsville, Md., carrying an “electro-optical” scanner that functions like a remote light meter with a camera-like lens protruding through the plane’s underside.

USDA’s Agricultural Research Service and the National Aeronautics and Space Administration (NASA) helped a company in Maryland develop the scanner system. As part of a cooperative research agreement with GEOSYS, Inc., of Plymouth, Minn., ARS is testing to see if the scanner’s images can be used to delineate consistent variations--high and low yielding spots--in farmers' fields to define “management zones.” The researchers will identify likely spots by light reflected from the foliage--the more foliage, the higher the expected yield.

The initial tests are being done with cornfields in Maryland and Minnesota.

Project organizers are using the scanner images, converted to computer maps, as overlays to existing maps, including crop yield maps. Their goal is to tie the images to a land feature, such as the capacity of soil at a specific location to hold water, or land slope, that may be causing consistent yield variations.

GEOSYS has expertise in analyzing imagery and handling other types of spatial (map-like) information for precision farming. As USDA’s chief scientific agency, ARS has expertise in remote sensing, yield prediction, and precision farming.

The CRADA is part of an ARS research project as well as a NASA project that also involves Cargill Research, a major agribusiness firm that hopes to use aerial and satellite imagery for precision farming. If the maps produced by this project were to be commercialized for precision farming, they would be available for farmers to load into computers on their tractors. Then as farmers drove the tractors across their fields, the computers would adjust the amount of fertilizer or the type and amount of seed, for example, for high- and low-yielding areas.

Scientific contact: Charles L. Walthall, ARS Hydrology and Remote Sensing Laboratory, Beltsville, Md., phone (301) 504-6074, fax (301) 504-8391, cwalthal@hydrolab.arsusda.gov.