Weeds can’t run, and they definitely can’t hide, thanks to new technology from Agricultural Research Service (ARS) scientists that helps farmers locate and eliminate weed patches.

Scientists in the ARS Water Management Research Unit at Fort Collins, CO, have developed two methods to assist farmers in site-specific weed management (SSWM), selecting the best management strategies for targeting weed patches in their fields.

Before investing in new technology, growers need assurance that the benefits will exceed the costs without compromising weed control. Computer programs like the ARS WeedSite can help farmers predict the results of specific SSWM methods and select the best options.

WeedSite is a software program that evaluates the effects of SSWM on irrigated corn cropping systems. It can be downloaded for free at: http://arsagsoftware.ars.usda.gov.

Growers draw weed maps of their fields, which the program uses to calculate the effects of various SSWM practices.

Plant physiologist Lori Wiles helped design WeedSite. She also worked with Fort Collins agricultural engineer Paul Irvin, Geographic Information System programmer Terry Giles, Robert Waltermire of the U.S. Geological Survey and several local farmers to develop and test a simple, low-cost system for mapping weeds in fallow fields.

By mounting a digital still camera and a Global Positioning System (GPS) unit on a tractor, a grower can take photographs and match them with GPS coordinates. The software identifies weeds within the photographs, then constructs a weed map with links to the photos. This enables the grower to easily view the weeds at specific locations in the field.

With a field weed map, a farmer can select appropriate herbicides, detect new invasions and monitor changes in existing weed patches.

Read more about the research in the August 2006 issue of Agricultural Research magazine.