(News article for July 8, 2023)
The first article in this series, which discusses different types of bamboo, is available here.
If you have a stand of bamboo that you want to get rid of, you have a couple of options.
You can hire someone with heavy equipment, such as a backhoe, to remove it. Most bamboo rhizomes (underground stems) are within the top 12 inches of soil. After stems and rhizomes are removed, the area can be mowed regularly to prevent bamboo from regrowing from remaining rhizome pieces. Alternatively, after it’s physically removed, new leafy shoots can be sprayed with an appropriately labeled glyphosate or imazapyr herbicide when they’re about 4 feet tall. If you use a glyphosate herbicide for this purpose, avoid formulations that have low concentrations of the active ingredient, such as “ready to use” products. Instead, choose, for example, a product that is 41% glyphosate and allows application of a 5% solution. See cautions below about using imazapyr herbicides.
If heavy equipment use isn’t practical for your situation, there is a possible herbicide route. Arsenal Applicators Concentrate or another approximately 53 percent (4 pound per gallon) imazapyr product used at a 1 percent rate (1.3 fluid ounces per gallon) is effective for killing bamboo.
It will likely take multiple applications of Arsenal or another imazapyr product to completely kill mature bamboo. Due in part to restrictions on how much can be used in one year, this may take more than one year.
One reason that – even with an imazapyr product – killing mature bamboo is challenging is that the dense canopy limits how much herbicide reaches the soil. Some herbicides work primarily or exclusively by contact with the top part of the plant (leaves, etc.), but a lot of imazapyr’s effect comes from its activity in the soil.
It’s very important to be aware that imazapyr-containing herbicides kill many other plants as well, including large trees. They are often used to selectively kill most plants other than pine trees (including oaks, etc.) in a pine planting.
Because of its activity in the soil, imazapyr can kill or damage plants even if it just gets in their root zone. We often estimate that tree roots grow to twice the width of the tree canopy, though they may extend farther from some trees. So, take great care to avoid damage to desired plants when using imazapyr-containing products.
When using any herbicide, be sure to read the product label. It’s preferable to do this before you buy it, so that you don’t buy it and then find out that it isn’t suitable for your situation. Almost all pesticide labels are available online. Follow label directions of herbicides and other pesticides carefully.
Let me know if you have questions.
Contact Mary Helen Ferguson.
Reference to commercial or trade names is made for the reader’s convenience and with the understanding that no discrimination or endorsement of a particular product is intended by LSU or the LSU AgCenter. In some cases, other brands are available.
The LSU AgCenter and the LSU College of Agriculture