Renovation and its effect on the populations of weeds in pastures
1938
Fuelleman, R.F. | Graber, L.F.
Renovation of permanent grasslands in Wisconsin is a method of pasture improvement involving the establishment of such dry- weather legumes as alfalfa (Medicago sativa), sweet clover (Melilotus alba and officinalis), and red clover (Trifolium pratense) in thinned pasture sods without plowing. Portions of 30 widely distributed bluegrass pastures in western and southwestern Wisconsin were renovated in 1929, 1934, 1935, and 1936. In 1937, the populations of species regarded as weeds were determined in the renovated areas and in adjacent areas of equal size not renovated. The 27 renovations of 1934 and 1935 reduced the total weed populations 85.7% in 1937, and likewise a reduction of 91.0% and 73.0% resulted from one renovation in 1935 and one in 1936, respectively. Nine years after the renovation of a 4-acre area of another pasture the total weed population was 93.6% less than that of the adjacent area of 4 acres not renovated. Ragweeds (Ambrosia artemisiifolia) and horseweeds (Erigeron canadensis) were the most generally prevalent species. In 30 pastures, renovation reduced ragweeds 85.7% and similarly horseweeds were reduced 92.1%. Where high percentages of the total weed populations of the nonrenovated portions of the 30 pastures consisted of ragweeds, the percentages of horseweeds were low and the negative correlation coefficient between such percentages was -78.
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