Q: I am trying to eliminate obnoxious volunteer Bradford pear bushes. Is there a way to kill the roots without waiting for regrowth and using weed killer.
A: You could dig the roots out, but I’m guessing that’s not what you want to do. Unfortunately, there is nothing that will make the roots die any faster than persistent application of a weed killer to the green leaves. Unlike some weed killers, glyphosate (Roundup, etc) translocates in the plant it’s sprayed on. That means it is transported by the sap a few feet from the application site. But my experience with the thorny, brushy form of Bradford pear is that there are plenty of roots that are many feet long. They will continue to send up green shoots for several months after a tree is cut down. Keep a sharp eye out for the green leaves. When seen, remove them immediately by clipping or using weed killer. The roots will eventually die.