Grass Response following Thinning of Broom Snakeweed

Abstract

Complete removal of broom snakeweed resulted in perennial grass production 833% of that on untreated rangeland after 1 growing season, and 712% and 300% the 2nd and 3rd yr, on a pasture heavily grazed and in poor range condition. On a moderately grazed pasture in good range condition, grass standing crop increased 42% the 1st yr, 81% the second, and 25% the third compared to untreated rangeland. Perennial grass production on the heavily grazed pasture was far below that on the moderately grazed pasture at the start of the study (40 vs. 454 kg/ha). After 3 yr, with complete broom snakeweed removal and no grazing, perennial grass production was comparable on the pastures once heavily and moderately grazed (1014 vs. 939 kg/ha, respectively).