Eliminating unwanted grass
When we moved into our house, we had a lot of bamboo growing on a hill beside a river. Every spring the bamboo shoots up and I have to cut it down weekly. Is there anything I can do to get rid of the bamboo permanently?
—Kevin, Pasadena, MD
Roger Cook replies: Too bad you can't hire a panda to do this job. They happily eat up to 35 pounds of bamboo a day. But with pandas in short supply, the only practical way to get rid of bamboo is to keep cutting it down to ground level or spray it with an herbicide, or both.
A small chainsaw will make short work of the mature stalks. Follow up with a weekly trim using a lawn mower. Also, keep an eye out for shoots beyond the perimeter of the grove; some bamboos will send underground runners, called rhizomes, up to 25 feet from their base. By next season, hopefully, your bamboo will be gone.
If you decide to use chemicals on your bamboo, glyphosate-based herbicides are usually effective. Be sure to follow the instructions exactly: They kill any plant they come in contact with, and you don't want them to reach the river. One approach I've found to be effective is to let the bamboo shoots grow to 2 or 3 feet in early spring, then spray them with herbicide. Then every time a new shoot reaches that height, spray again.
Here's another option to consider: Rather than eliminate your grove entirely, cut it back to a manageable size, then contain it with a physical barrier. One off-the-shelf product uses thick interlocking polyethylene sheets buried about 3 feet in the ground. Containment systems do require vigilance because rhizomes will try to grow over the barrier. If any of them succeed, you'll need to remove them.
By the way, not all bamboo is such a headache. "Clump-forming" bamboo is not invasive and doesn't call for heroic containment efforts.