Bamboos are perennial members of the grass family and are often one of the most difficult to control escaped ornamentals. They are distinguished from other grasses by their woody stems, branched growth, and often large size. They can grow anywhere from one to seventy feet tall. While often considered beautiful, they can quickly turn into a homeowner’s worst nightmare if not properly maintained. Once established, bamboo can take over landscapes, stream banks, and woodlands.
The South Carolina Exotic Plant Pest Council lists golden or fishpole bamboo (Phyllostachys aurea) as a severe environmental threat. Plants in this category have the capabilities of being highly detrimental to the composition, structure, and function of natural areas from South Carolina’s Piedmont through the Coastal Plain.
Non-native invasive species, such as bamboo, were introduced to decorate homes and gardens. Over the years, they have escaped cultivation and have infested natural areas. These non-native plants have an advantage over native species. They can easily out-compete native plants for habitat because they grow in environments that lack natural controls from diseases, insect pests, and grazing by wildlife. This causes an imbalance in the ecosystem and threatens the biodiversity of the area.
There are about 1,200 species of bamboo, with many of these being sold in the nursery trade. There are two basic types of bamboo: clumping and running. Clumping bamboo species grow in large clumps and are relatively slow in spreading. Their root system can be quite large and compete with surrounding plants. This type can often be removed by digging up the offending plants. Unfortunately, many of the more popular types of bamboo sold in the nursery industry are the more invasive, spreading types. Running bamboos can be problematic once established, as they spread by thick, tough, underground stems called rhizomes. These rhizomes can spread more than 100 feet from the mother plant and are very resistant to adverse environmental conditions and most herbicides.
Every effort should be taken to control a bamboo infestation in its entirety. Because bamboo is so aggressive, it can re-establish rapidly if any small rhizome section is left after digging. Homeowners with bamboo infestations must be patient, as this weed requires an intensive control program over several years.
The first step in controlling bamboo should be to remove as much of the root mass and rhizomes of the plant as possible. This can often be done by hand with small infestations, but larger problem areas may require the use of power equipment. Containment is also a fairly effective method of controlling bamboo but must be monitored regularly. Because the rhizomes of bamboo are shallow, growing less than one foot deep in the soil, a barrier made of concrete, metal, high density polyethylene (HDPE), or pressure-treated wood installed about 18 inches deep has proven to be effective. However, the wood will eventually rot, and the concrete may crack and allow the rhizomes to pass through. Bamboo rhizomes are not stopped by barriers but are merely reflected. Because of this behavior, the areas surrounding the barriers should be monitored regularly for escaped rhizomes that should be cut back.
Regular mowing is another method that can help control bamboo over time. Because bamboo is a grass, it can tolerate occasional mowing but does not tolerate frequent mowing. Mowing practices similar to that in a home lawn can eventually deplete the bamboo rhizomes and offer some control. Two to three years of regular mowing are often needed to see results.
A final and often necessary method of control for bamboo is the use of herbicides. A non-selective herbicide with the active ingredient glyphosate is the best option for homeowners. Glyphosate has very little residual soil activity and will only kill plants that receive direct contact. For glyphosate to be effective, the bamboo must be mowed or chopped and allowed to regrow until the new leaves expand. A 5% solution of glyphosate should be applied to the newly expanded leaves. Buy a 41% glyphosate product and follow label directions for mixing. Keep in mind that one application of glyphosate will not eradicate the bamboo infestation. It can potentially take two to three years to gain complete control.
Examples of products with concentrated (41% or more) glyphosate packaged in homeowner sizes are:
- Roundup Original Concentrate,
- Roundup Pro Herbicide,
- Martin’s Eraser Systemic Weed & Grass Killer,
- Quick Kill Grass & Weed Killer,
- Bonide Kleenup Weed & Grass Killer 41% Super Concentrate,
- Hi-Yield Super Concentrate,
- Maxide Super Concentrate 41% Weed & Grass Killer,
- Super Concentrate Killzall Weed & Grass Killer,
- Tiger Brand Quick Kill Concentrate,
- Ultra Kill Weed & Grass Killer Concentrate,
- Gordon’s Groundwork Concentrate 50% Super Weed & Grass Killer,
- Zep Enforcer Weed Defeat III,
- Eliminator Weed & Grass Killer Super Concentrate,
- Monterey Remuda Full Strength 41% Glyphosate,
- Knock Out Weed & Grass Killer Super Concentrate,
- Southern States Grass & Weed Killer Concentrate II,
- Total Kill Pro Weed & Grass Killer Herbicide,
- Ace Concentrate Weed & Grass Killer.
Do not apply these products directly to water or to areas where surface water is present. For bamboo control next to creeks, lake basins, wetlands, or other water sources where spray drift will contact the water, choose a glyphosate product labeled for use near water, such as Eraser AQ, Hi-Yield Killzall Aquatic Herbicide, Rodeo, Pondmaster, Aquamaster, or Aquapro. Aquatic formulations of glyphosate may be mixed with a non-ionic surfactant, such as Hi-Yield Spreader Sticker Non-Ionic Surfactant or Southern Ag Surfactant for Herbicides to improve control. When using herbicides, please be sure to follow all label instructions.
While bamboo control is not impossible, it can often seem that way. Staying on top of the problem is one of the most important things to remember. An intensive control method over several years will be necessary to eradicate a bamboo infestation. One of the best methods of control is prevention. Always do your homework before planting bamboo and encourage your neighbors to do the same.