An experiment was conducted near Scottsbluff, NE, to assess three technique
s for establishing perennial grasses in pasture sites and to evaluate the e
ffectiveness of five perennial grasses compared with herbicide or mowing fo
r Canada thistle control. Perennial grass density 9 mo after seeding and pe
rennial grass biomass 12 mo after seeding both followed the same trend, ind
icating that preplant rototilling improved perennial grass establishment. A
fter 3 yr, Canada thistle control was greater than 90% in plots where peren
nial grasses had been established utilizing preplant rototilling, and compe
titive grasses were as effective as yearly applications of clopyralid at 0.
55 kg/ha for controlling Canada thistle. Averaged across two studies conduc
ted for 3 yr, hybrid wheatgrass, intermediate wheatgrass, Russian wildrye,
tall fescue, and western wheatgrass provided 85, 74, 76, 78, and 66% Canada
thistle control, respectively.