Argentina is currently reviewing applications for the importation of U.S. citrus, pork and other commodities. NAWG has long supported basing all such international standards on sound science and fears that the Senate approved language would severely undermine this effort an effort that the U.S. has, in the past, lead around the world. At the present rate of infestation, Canada thistle will surpass leafy spurge in total acreage by 2002, Zollinger says. The most recent data suggests it already infests more than 900,000 acres, up 300 percent since 1992. Zollinger says both NDSU Extension Service staff and the North Dakota Department of Agriculture have received numerous phone calls from landowners concerned with lack of Canada thistle control in neighboring cropland, pasture and CRP land.
State law requires every citizen to control the spread of noxious weeds on their land.
If noxious weeds are not properly controlled, complaints should be made to county or city weed boards. Control methods include hand-cutting, mowing, controlled burning and herbicides. Canada thistle is a perennial, so entire plants must be killed to prevent regrowth from rootstock, says Zollinger. Research on biological control of the weed is under way. Seeding a cover crop can provide an array of advantages where heavy rains have destroyed crops in Minnesota and North Dakota farm fields.