Mowing small trees such as hedge and locust seems to "just make them mad." They sprout back quickly and with more vigor than before. To mow and kill the trees in one trip, Jack Delaney, Greentop, Mo., mounted a sprayer on his rotary mower. The liquid herbicide is gravity-fed on top of the mower blades. He also installed an electric shut-off switch. "I'm seeing about a 90 percent kill rate on locusts, hedge and multi-flora rose in pastures and CRP," reports Mr. Delaney.