Good managers might be able to pick up premiums just by doing what they do well, keeping their fields weed-free. They'll also be helping to keep our native ecosystems healthy and clear of foreign invaders.

Under the North American Weed-Free Forage Program (NAWFFP) and other similar programs, 54 weeds are classified as noxious. Growers whose fields are certified as free of these weeds can earn premiums of as much as $25/ton.

Weed-free certification got its start in Montana, Wyoming and Colorado in the mid-1990s but has since spread to 16 states. The purpose of the programs: keep noxious weeds from spreading to public lands.

“Noxious weeds are invasive,” explains Adrianne Peterson with the North American Weed Management Association. “They take over our natural flora and can invade a healthy natural ecosystem. A noxious weed invasion is worse than a toxic spill. Some seeds, like field bindweed, are viable for 50 years.”

Noxious weeds spread via air, water, birds, hay, vehicles, fur, and basically any human activity that disturbs soil. Houndstounge can actually stick to an animal's fur and in turn be carried onto public lands. Horses and other animals can also excrete seeds that have been ingested.

Prevention is the most important form of control, says Peterson. Stop the invasion before it starts. One small way to prevent invasions of noxious weeds is to restrict hay use by horse owners who enter public lands for recreational riding.

Horse owners are encouraged to feed their horses hay that's been certified as weed seed-free for three to 10 days prior to entering public lands in the West, says Peterson. The horse owner must either bring the horse's hay or buy it on site if it's available.

Ten of the 16 states with certification programs for weed seed-free forage, including Minnesota, Wallowa County in Oregon, and the Canadian province of Alberta, all certify in accordance with NAWFFP. In some states, the program is run through the agriculture department, while in others it's run through a trade association.

Certifiable forage products include alfalfa hay, alfalfa-grass hay, forage pellets and cubes, grain hay, grass hay and straw. Growers interested in having their fields inspected call the certifying organizations in their states before harvesting the fields.

Ben Lang is an inspector with the Minnesota Crop Improvement Association (MCIA), Minnesota's certifying organization. “Certification is done based on an inspection of the field and is done within 10 days of harvest,” Lang says. “We walk the field to determine whether it's free of noxious weeds.

“If any of the 54 noxious weeds are present in the reproductive stage, the field will be disqualified,” he adds.

Lang notes that most top managers have fields that would qualify. “They may have to cut out weedy areas or spray in advance,” he says, but with a little work, their fields would pass.

Sometimes a field will fail on the first pass. If that happens, the grower can make a correction and have it reinspected. Lang estimates that about 75% of the fields he surveys eventually pass inspection.

Jerry Hermann, Georgetown, MN, is another inspector for MCIA. While the program is run somewhat differently in different states, the way it works in Minnesota, Hermann says, is that once a field passes inspection, the grower gets a listing in the MCIA directory. A horse owner looking for hay that's certified as weed-free locates the grower and the two then negotiate a price.

The market for weed seed-free hay is not well-defined, but Hermann and others say most, if not all, of the certified hay is being sold.

“At any one time, a couple hundred growers in Montana are certified. Some come back year after year,” says Tonda Moon, weed specialist with the Montana Department of Agriculture.

In 1990, Montana growers produced 16,637 tons of weed seed-free forages. By 2003, total production had more than doubled to 40,349 tons.

In states newer to the program, such as Minnesota, the number of producers raising certified hay is far lower, but growing. And while theoretically a field with a noxious weed could pass inspection if the weed has not reached the reproductive stage, for all practical purposes, the fields need to be nearly perfect.

“When I pass a field, I put my name at the bottom of the form,” says Hermann. “The reputation of the Minnesota Crop Improvement Association and my reputation are on the line when the certified hay is inspected in another state.”

Occasionally, a certified bale will be rejected once it reaches its final destination. If that happens, the grower is responsible. But problems are not common.

“Someone with good management and weed control could probably pick up a premium,” says Hermann, who also inspects wheat and oat fields for the mulch portion of the program. A rapidly growing demand area, weed-free certified mulch is used by state and county agencies on roadsides.

States participating in certification programs are: California, Colorado, Idaho, Kansas, Minnesota, Montana, Nebraska, New Mexico, Nevada, North Dakota, Oklahoma, Oregon, South Dakota, Utah, Washington and Wyoming. Two Canadian provinces, Alberta and British Columbia, also have programs.

For a list of banned noxious weeds and contacts for the above-mentioned state programs, go to and click on Weed Free Forage.