VIRGINIA CITY - From the peaks above this historic town, it's easy to imagine miners discovering gold and the dramas that played out between vigilantes and road agents. Even today, mules wait near the mouth of a mine. A tailing pond reflects the sky as thunderclouds build over the Gravelly and Greenhorn Ranges.

"It's an incredible view up here," Rebecca Kennedy observed on a recent hike.

But Kennedy, an undergrad at Montana State University in Bozeman, wasn't in Madison County to admire the scenery or ponder history. With a pack on her back and global-positioning equipment in her hand, she was mapping spotted knapweed and other vegetation.

In a new twist, her finely accurate maps, and video recording where weeds are on the ground, will be compared to high-tech remote-sensing images shot from a plane passing more than a mile overhead.

The project will help determine if its possible use remote-sensing technologies to detect noxious weeds over vast landscapes relatively quickly.

The MSU TechLink Center, based on the university campus and funded by the National Aeronautics and Space Administration (NASA), the Department of Defense, and the Department of Energy, put the project together. TechLink's mission is to match government technology with private enterprise; more than a dozen companies and government entities are involved in the weed experiment.

Two systems of remote-sensing imaging "can capture information well beyond what is visible with the naked eye," says Dan Swanson, project coordinator and direct of agriculture initiatives at MSU TechLink. "As such, they offer the promise of mapping weeds from airplanes and even from space. But can they deliver?"

Doing the legwork on the ground, Kennedy and five others collected information on 4 square miles of weedy terrain just west of Virginia City. The week before, they did the same near Twin Bridges.

"Without understanding where these weeds are or where they fit across the landscape, it's impossible for us to develop strategy," says Roger Sheley, a principal investigator for the project who is also an associate professor at MSU and noxious weeds specialist for MSU Extension.

Leafy spurge and spotted knapweed are the two primary weed pests in Montana and the surrounding region. Sheley believes they might be the No. 1 environmental threat in the West today. Leafy spurge infests at least 29 states and costs Montana, Wyoming and the Dakotas an estimated $144 million every year. Spotted knapweed infests all Montana's counties and is spreading rapidly.

"State and local weed-control associations have identified the need for more efficient weed mapping and control systems, due to the number of large ranches and vast stretches of public land in the region," says an outline of the weed experiment. "Current methods... are slow, expensive and do not offer economies of scale over large areas."

For that reason, the project tests the use of the two remote-sensing technologies that Swanson refers to - multispectral and hyperspectral imaging. The experiment was set in Madison County and the Ruby River drainage because of their weeds and the initiative of area residents.

The heart of the experiment began beating in early August, when Positive Systems of Whitefish flew a plane over the Virginia City and Twin Bridges plots. The plane carried a multispectral camera system that took digital aerial photo images from about 7,500 feet above ground. Crewmembers then walked those areas and mapped the weeds they saw. Precision Partners of Fargo, N.D. took a video record of weeds in the area.

Analysts are now comparing the vegetation recorded on the maps, video and digital imagery to see how closely they correspond. Global positioning (GPS) assures accuracy within about 3 feet.

Preliminary information should be available within a year, says Rick Lawrence, assistant professor of remote sensing at MSU and another principle investigator. The information should be "completely mined" within two years, he says.

If the experiment works, the participants expect remote sensing to be a valuable tool in fighting noxious weeds throughout the West. Not only will it help managers plan strategies, but also it will help them understand why the weeds are spreading so successfully. The collaborators hope the technology will be commercialized and spread far beyond the Madison Valley.

"This new tool will be unbelievably useful," predicts Kim Hudson who works for the Madison County Weed Board and supervises crews that spray weeds on Bureau of Land Management (BLM) land. Hudson currently has to rely on hikers and others who frequent the backcountry to let hi know about weed infestations he hasn't discovered himself.

The weed experiment costs about $250,000, shared by the participants, including Earth Search Science, Inc., Turner Enterprises, Precision Partners, Inc., Hyperspectral Sciences, Inc., Red Hen Systems, Inc., Dow AgroSciences, Inc., Positive Systems, Inc., Madison County Weed Board, BLM, Ruby River Council, MSU Extension Service, MSU TechLink Center, Department of Land Resources at MSU-Bozeman, and the U.S. Forest Service.

This news article was also published in The Prairie Star, September 1999, page B75, "Project Tests Novel Method of Mapping the Weeds of Madison County."

Back to Top