How to kill bamboo?

How To Kill Bamboo

Photo: room-decoratingideas.com

Some people love bamboo, but far more people loathe it. That’s because they plant this fast-growing, fast-spreading monster as a screen so they can’t see their neighbors. Then in about two weeks, they can’t see themselves either. Bamboo comes up everywhere, until they cry in desperation to Grumpy, “How can we kill this damn bamboo?”

Well, it’s easier than you might think. But to understand why, you need to know a little more about it. Bamboos are giant, woody grasses. Some are clumping and cause no problems. But most are running, spreading rapidly underground by thick rhizomes — sometimes as thick as your forearm — torpedoing unseen through the soil. From the rhizomes grow canes, called culms. Giant bamboos are the fastest growing plants on Earth, even faster than kudzu. Some culms can grow four feet a day!

Image zoom emBamboo rhizome. Photo: bamboocraft.net/em

Starting each spring, culms grow to their full height in about 60 days and grow no taller after that. Culms with small root systems may grow to 10 feet. Culms with large, established root systems may grow 70 feet tall. Individual culms live for about 10 years and are then replaced by new ones.

If bamboo has taken over your yard, the knee-jerk solution is to get a tank of Roundup and spray those suckers down! This will not work. You may kill the top growth, but that huge root system will sprout again next spring.

What you need to do to kill bamboo is to take advantage of the fact that new culms only sprout in spring. They look like the tips of asparagus spears. Wait until they’re about a foot tall and either cut them off at the ground or push them over with your foot. It’s easy. They will not grow again.

Then cut all mature canes to the ground. If your neighbor has bamboo, make sure he does it too. Every spring, watch for new culms sprouting in spring. Push every one over. If you and your neighbor keep doing this, eventually you’ll starve the root system and the bamboo will die.

Now you know. You’re welcome.

By Liz Crumbly

Bamboo can be beautiful, whether it’s on your floor in pristine tan planks or sitting on your kitchen counter as a vibrant green shoot contained in a pretty flower pot. It’s when invasive bamboo breaches its boundaries that it becomes less a thing of beauty and more of an unmanageable menace. I’m talking about when a single stalk becomes a forest in your backyard. I’m going to explain how this phenomenon occurs, how to prevent it and how to deal with it when you find yourself overrun with this perennial evergreen.

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It’s possible for a single decorative bamboo shoot to expand to a dense stand in just a few growing seasons. If you have bamboo growing on your property unchecked, you must take steps to contain or eliminate it before it becomes a veritable forest.

1. How It Happens

Many of the varieties of bamboo available in local nurseries spread via rhizomes. Rhizomes that spread in a horizontal manner near the soil surface are known as running or monopodial forms, according to the ABS (American Bamboo Society). These fast-spreading rhizome systems account for the rapid growth we see when invasive bamboo has been planted outside and left to its own devices.

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Many bamboo varieties spread via rhizomes just under the soil surface.

Some varieties can grow up to nearly 48 inches per day in ideal conditions, according to the ABS. Stalks, the society asserts, reach their complete height in one season. Given the lightning speed with which this resilient grass grows and spreads, it can quickly become a nuisance if you didn’t actually intend to install a large amount of it.

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Bamboo reaches its full height in one season, according to the American Bamboo Society. Some of these stalks are higher than a one-story house.

2. How to Prevent the Invasion

The best way to avoid an invasive bamboo forest in your backyard is simply never to plant it. Just don’t give in to the temptation of sticking that cute shoot in the ground after you’ve tired of looking at it on your kitchen counter. Either get used to seeing it as an installation in your house, or gift it to its next owner to enjoy indoors.

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If your bamboo has been growing for a few years, don’t be surprised to find larger stalks like this one measuring two inches in diameter.

3. How to Stop a Spreading Forest

Your first reaction when you realize your bamboo stand is out of control may be to reach for copious amounts of herbicide. My first reaction, when I realized my new farm was home to a veritable bamboo preserve with stalks as thick the pipes under my kitchen sink, was to release a prolonged scream of pure desperation. As it turns out, chemicals aren’t your best bet, and neither is despair. The processes of containing and eradicating bamboo are both decidedly mechanical tasks.

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Smaller bamboo stalks like this one can be eliminated if you simply step on them and bend them to the ground.

If you simply wish to stop your existing stand from spreading any farther, the ABS recommends making a “rhizome barrier” by digging a three-foot deep trench around the stand. Be mindful of the tenacity of rhizomes intent on spreading, however: This trench, the society states, must be filled with loose gravel or concrete.

If you’ve decided to take the plunge and rid your property completely of invasive bamboo, just be aware you’re embarking on a process that will take some time. Plan on bending smaller shoots completely over and cutting larger ones near the ground. Do this toward the end of your winter season. After this first round of eradication, if you’re really feeling exhausted, you can spray an herbicide like Roundup on the ground surrounding the bent shoots to kill the rhizomes. It’s possible, however, with some tenacity to complete the process without using these harsh chemicals: When new shoots emerge, simply repeat the process of bending or cutting them. Continue doing this until the rhizomes, exhausted in their unsuccessful efforts give in and stop producing new shoots.

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Eradicating bamboo is a multi-step process. You’ll need to bend smaller stalks over and cut larger ones near the ground in late winter. When new shoots emerge, repeat the process until the rhizomes are exhausted. Here, stalks have been bent and cut and new ones have emerged.

So remember that the best way to contain bamboo is to enjoy it as a decorative houseplant. If you do find yourself in a situation where it has become invasive, you can choose to contain it or completely get rid of it, but be aware that each avenue will take some time and physical labor.

Bamboo is beautiful, but it is extraordinarily hardy and prolific, and any use of it in an outdoor setting should be done with a careful eye toward management.

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Dead bamboo, which turns a dull tan color, is easy to differentiate from the vibrant, green live version.

Images used with permission, courtesy of Liz Crumbly

What Kills Bamboo?

Where Does Bamboo Grow?

Bamboo species come from a variety of habitats all over the world. There are tropical bamboos that grow in moist, hot areas and others that grow on cold mountain slopes. Canada and Europe don’t have any native bamboos, although bamboo is grown in both areas. Generally speaking, bamboo will grow in any USDA zone above Zone 5, and may grow in Zone 4 with protection.

Is Bamboo Considered Invasive?

Bamboo’s potential for being invasive depends primarily on the species and/or variety. Although there are more than 1,000 species of bamboo, the Phyllostachys group is by far the most likely to become invasive. Bamboos in this group have an extremely fast growth rate. For example, mature Phyllostachys edulis ‘Moso,’ a giant timber bamboo, can grow several feet in a single day.

What Bamboo is Most Invasive?

Bamboo performs differently depending on the USDA Zone and growing conditions. However, these are among the most likely to become invasive in multiple areas:

  • Phyllostachys rubromarginata; Red Margin Bamboo
  • Phyllostachys aurea; Fishpole Bamboo, Golden Bamboo, Monk’s Belly Bamboo, Fairyland Bamboo
  • Phyllostachys vivax; Chinese Timber Bamboo
  • Phyllostachys aureosulcata; Yellow Groove
  • Semiarundinaria fastuosa Viridis; Viridis, Green Temple Bamboo
  • Chimonobambusa quadrangularis Suow; Golden Square Stem

Why Does Bamboo Grow so Fast?

To understand bamboo’s growth rate, you must remember that is a grass. A bamboo shoot (culm) contains all the cells it will ever have. To grow, it doesn’t need to build new cell walls, it need only fill the existing cells with water, which elongates the cells. What fuels the growth is the size of the root mass, so mature bamboo clumps can grow at unbelievable rates.

Running vs. Clumping Bamboo – What’s Different?

Bamboo comes in one of two kinds, clumping or running. Clumping bamboo grows from individual rhizomes, and each rhizome becomes a single culm. Running bamboo, like many grasses, sends out horizontal rhizomes. Multiple culms can arise along the length of the rhizome. In addition, each rhizome has multiple buds to help it spread horizontally. Each bud becomes a new rhizome.

How Do I Rootprune Bamboo?

Bamboo runners grow primarily in the top five to six inches of soil. The root mass in the center of the clump does grow deeper but doesn’t send out rhizomes. Start by digging a permanent six-inch deep trench around the bamboo. Twice a year, use a sharp shovel to make vertical cuts all along the edge of the trench. This will cut off the bamboo rhizomes; remove all pieces and burn.

Can I Starve Bamboo Roots?

It’s hard to starve bamboo roots without starving the entire plant. However, if you want to remove the bamboo entirely, cut it to the ground. Repeat the process of cutting it to the ground every time it starts to sprout again. You should also withhold water and fertilizer. This may eventually exhaust the food reserves in the roots and kill the plants.

How Do I Burn Bamboo?

Ammonium nitrate fertilizer is sometimes used to “burn” bamboo. Cut the culms to the ground. Spread fertilizer generously over the bamboo clump. Cover with transparent plastic. The combination of high-nitrogen fertilizer, heat from the sun and lack of oxygen should kill the bamboo. After a few weeks, dig up the clump – make sure you get all the rhizomes, as otherwise it’s possible one or more may sprout.

Can I Set Fire to Bamboo?

Bamboo will burn, but setting a fire in a suburban garden is probably not a good idea. Some gardeners do use hand held propane torches for small sprout removal to keep a clump under control. For a large acreage of bamboo, it would be wise to consult the local division of forestry or the fire department. They may even be willing to use your bamboo as a “practice burn.”

Can I Kill Bamboo with Herbicides?

Glyphospate and Imazapyr (Roundup and Aresenal) are the two herbicides most likely to be effective against bamboo. Unfortunately, neither is organic and Arsenal is likely to damage adjoining plants. Acetic acid (Burnout) may be a better choice as a bamboo killer. Use a 20 percent concentration, preferably on a hot day. To use these solutions cut the bamboo culms one at a time and immediately paint the cut with the herbicide.

Will Digging up Bamboo Kill It?

The answer is a qualified yes. Yes, if you dig up the entire plant – for large plants, this may mean a backhoe. Yes, if you get every tiny little fragment of rhizome. This means literally sifting the soil to make sure you haven’t missed any pieces. Yes, if you continue to check back in the area for anything you might have missed and immediately remove it from the soil.

Can I Smother Bamboo Roots?

Smothering the roots may be successful in getting rid of a clumping bamboo. To smother, cut the bamboo off at ground level and cover with a heavy tarp. Weight the edges down with large rocks or boards to shut out all the light. Running bamboos may just send rhizomes out past the edges of the tarp, so smothering is less likely to be successful.

Can I Kill Bamboo by Girdling It?

Girdling is cutting a layer of bark all around a tree. Since trees get their nourishment through this layer (the cambium), girdling interrupts the flow of nutrients and kills the tree. Girdling doesn’t work with bamboo, because it isn’t a tree and doesn’t have bark or get its nourishment this way. Finally, bamboo spreads from the roots, which would be below a girdling cut.

Does Cutting Bamboo Down Kill It?

Just cutting bamboo down is similar to mowing your lawn. The root mass is still intact and will promptly send water and nutrients into the underground rhizomes to create a spurt of new growth. If you cut it down and consistently cut back new shoots the minute they appear, you might eventually be able to exhaust food reserves in the roots, which may then kill the clump.

Can I Kill Bamboo with Bleach?

There is little research on killing bamboo with bleach (sodium hypochlorite), but common household bleach is used as a general weed killer by some gardeners. It is most likely to be effective if you use it full strength. Cut the bamboo culm to the ground and spray or paint the bleach over the open end immediately, just as you would with an herbicide.

Can I Dig Out Bamboo with a Backhoe?

If you are dealing with a large stand of bamboo, you must nearly always use something like a backhoe to dig it out – it’s simply too big a job to do it by hand. Make sure you have a qualified operator or know how to do it yourself. In suburban areas, you might need a permit. Always confirm the placement of electric, water and gas lines prior to digging.

Can I Kill Bamboo with Organic Methods?

Combination methods are most likely to be effective in killing bamboo. The organic methods mentioned above can be used in combination for best effect. For example, cut the bamboo to the ground, spray with bleach or acetic acid, and smother with a tarp. Once the clump is damaged or dying, dig it out by hand or machine – ideally, you should sift the soil.

Will Any Animals Eat Bamboo?

Controlling fast-growing plants by allowing animals to graze or eat them is a common practice around the world. The animals that will eat bamboo include pandas, bamboo lemurs and bamboo rats, which eat only bamboo. Chimpanzees, gorillas and elephants will eat the young bamboo shoots (as do humans). Animals like cows, horses, sheep and goats will not graze on bamboo leaves or shoots.

Can I Kill Bamboo by Overwatering?

If you have bamboo in a pot or container, overwatering is actually one of the most common ways to kill it. Bamboo planted in the garden is a different story. Just running water continuously over a clump won’t have an effect. In order to kill a bamboo planted outdoors, you would have to be able to submerge the roots and keep them underwater for a couple of weeks at least.

How to Prevent Bamboo From Spreading

It’s a fact that bamboo can be one of the most interesting and most beautiful forms of landscape to have in your property. Whether you live in a private estate at the heart of a large chunk of land or you simply want to use landscaping to surround the outskirts of your property, the task can be done easily and nearly effortlessly. It’s so effortless, in fact, that you will soon find yourself living with too much bamboo to deal with. While this plant can be a great addition to the look and feel of your property, their amazing growth spurt can literally overshadow the good things. To prevent this while keeping the nice landscape, you need to carry out precautionary measures to prevent bamboo from spreading.

Methods

There are many ways to get started. First, you will have to assess the amount of landscape and the length of the perimeter surrounding the actual preferred bamboo plantation. It’s not advisable to allow marginal space before setting the rhizome barriers, which will be discussed further one. The reason being is that bamboo will grow into these marginal areas, anyway. It’s more advisable to clump off the overgrowth right where it should be cut.

There are basically two ways of stopping an overgrowth of bamboo in your property. First of which is through clumping. The second method is by means of using running type rhizome barriers. Keep in mind that each method is entirely different from the other, and uses different materials to achieve a similar goal.

Clumping

A clumping bamboo is grown very near the plant’s base, where the short rhizomes are. There are many running bamboo varieties that are difficult to control because their growth circumvent the barriers. The best way to deal with this is to determine which type of bamboo you have in your property. It’s greatly advised that you plant bamboo that are easier to control to begin with. However, if the problem is already right in your doorstep, literally, all that is left for you to do is control the overgrowth.

Rhizome barriers are very effective ways of preventing overgrowth in areas where typical clumping varieties will not work. You should ask an expert for more details regarding this. Look for a rhizome barrier installer online and find a contact number. Drop them a line and discuss the bamboo issue at your place over the phone or personally, after scheduling an inspection.

Root control, containers and gardening

Bamboo containers are another great way to prevent bamboo from spreading. Overgrown bamboo also tend to loom over your property, so additional methods like this are a good way to go. Aside from these methods, digging a trench 18 inches deep should be able to do the trick. Dig a little less deep, however, and persistent roots may still manage to breach the gap somehow. This can be especially frustrating if you’re also into gardening. In that case, bamboo root control should also be one of your top concerns.

Since bamboo is very persistent plants and can grow out of control, despite your effort, it’s a must to get a professional crew to deal with your bamboo. Remember that this is landscaping we’re talking about. It should be constructive – not frustrating.

The key to successful bamboo control is learning how to prune the rhizomes. Removing shoots and canes above ground level merely hides the evidence; it does not prevent spreading. Although plastic Rhizome Barrier is now used extensively and sold by many vendors, including us, we believe root pruning should be the first option. Any bamboo grower should familiarize themselves with basic root pruning techniques, even if using barrier. Providing a thorough education is one of our top priorities. We believe anyone who sells bamboo has an obligation to give clear and accurate information about the nature of bamboo and how to master it. Consider the following proactive methods for taming bamboo.
Part I: Root Pruning
Bi-annual root pruning around the edge of a running bamboo is the most effective way to achieve long-term control. Fortunately, rhizomes are usually very shallow rooted and prefer to grow in loose topsoil 2-5 inches beneath the surface. Root pruning is achieved by working around the bamboo with a sharp spade, driving it into the ground and removing the wayward rhizome. One can generally feel the rhizome as the spade cuts it. The rhizome can be cut back to about two feet from the parent plant, or to wherever bamboo growth is desired. It is necessary to leave some rhizome attached so that the bamboo can produce healthy new shoots in the spring. Cut off and completely remove the rhizomes that are discovered outside of their designated area. Small segments of rhizomes can rejuvenate so make sure to be thorough. The smaller, leftover feeder-roots will not grow into new bamboo plants. A ripper on the back of a tractor works well for edging long distances.
Although digging rhizomes seems challenging, with careful planning, conditions can be created that simplify this task. One can maintain a shallow trench (8-12 inches deep by 12 inches wide) to control the spread of rhizomes. Check for creeping rhizomes a couple of times in the late summer and early fall to see if any of them have tried to cross the trench. If so, cut and remove them. After doing this a few times one learns where the rhizomes are most likely to be, and therefore, where to check more frequently. Because rhizomes are shallow, they often poke out the side of the trench. If a trench is impractical for the area, it can be filled with a loose media, such as sand, which is easy to dig into for root cutting. If one side is inaccessible for pruning, one can install an open-sided barrier and root prune along the edge that is easy to access.
Planting bamboo on berms or in raised beds is useful because the loose, rich topsoil provides a healthy growing area and the rhizome can predictably be found in the upper layer. Once the rhizome comes out of the edge of the berm it can be easily found and cut. Loose topsoil makes it easy to remove long runners. Bamboo has difficulty running down a slope or over a ledge and often exposes itself in the process. The use of river rock or pebbles to decorate the ground beneath the bamboo is not advised. Fallen leaves will quickly cover them and ultimately the bamboo roots will engulf them. This makes root pruning or digging in the future much more difficult. Tools will blunt and break against rocks. The occasional well-placed boulder or cement pagoda is a good compromise.
Well thought maintenance plans are often a combination of these techniques. For instance, creating a raised berm, trenching around the bamboo, and then root pruning is more effective than only trenching or root pruning. Combining and mastering all three techniques will give you the most experience and control over your bamboo.
If you plan to use barrier to control the spread of running bamboo, it is important to install it properly to ensure its effectiveness. Please read over the installation steps below. OPEN SIDED BARRIER is a good choice for long term health and bamboo control. It requires annual root pruning on the side left open. There are some advantages to doing this, mainly it will prevent bamboo from becoming too root bound within an small, enclosed space. It also assures that the planting area has adequate drainage which is especially important in certain areas that collect a lot of water in the winter. It is often used to create a border along a fence line or property line if your main concern is keeping good neighborly relations. An open-sided barrier (half circle or U-shape) will focus the rhizomes in one direction, thus reducing and simplifying the area that needs annual pruning. This is a good technique to use for small areas (less than 30 feet total circumference), or if you are planning to dig divisions of the original plant at a later date. The stainless steel clamp is not needed for these applications. See this link for installation tips: Installing an open-sided barrier
Check around the perimeter of the barrier once or twice a year, removing any rhizomes trying to escape over the top of the barrier or rhizomes that track just underground along the edges. Avoid digging too close to the barrier with a sharp tool or anything that could potentially damage the barrier, and never allow a mower or any other machinery to damage the protruding edges. This could cause the rhizomes (underground spreading stems) to escape undetected. The use of bark mulch or other loose, organic substances spread 2 to 5 inches deep over the top of your planting area within the barrier encourages the rhizomes to spread just inches below the surface, making them very easy to locate and prune. It also makes for a healthier bamboo! It is recommended that you annually prune any rhizomes that track along the edges of your barrier as, over a several year period, they can build up a tremendous amount of pressure which, in some cases, can eventually cause the barrier to fail.
RHIZOME SAND TRAP


Photo © Noah Bell, Bamboo Garden
3 yr old daughter, Iris, packing down the sand in the rhizome sand trap designed for root pruning. Phyllostachys bambusoides “Japanese Timber Bamboo”

Photo © Noah Bell, Bamboo Garden Caution! Rhizome crossing
leaf mulch pulled away to reveal several rhizomes.

How to install the Bamboo Shield® to control bamboo.

Are you tired of dealing with bamboo in your yard? Preventing the spread of bamboo is easier than you may think.

Bamboo Shield utilizes High Density Polyethylene in 60 mil thickness or greater to control bamboo and remove the need for constant maintenance. Metal barriers rust and concrete cracks. High Density Polyethylene in thickness of 60 mil or greater has proven results in the containment of bamboo.

Step One: Bamboo is a colony plant and left unchecked, the bamboo roots travel farther than most people expect. Rhizome growth can extend outward the same distance as the cane grows tall. The above ground growth represents only 50% of the total biomass.

Step Two: When bamboo becomes established, it can spread into unwanted areas. Root growth can occur much farther out than the above ground canes. Bamboo roots run parallel to the surface, typically in the first 18” or less of soil.

Step Three: To control the bamboo, you want to cut unwanted growth at ground level. Existing growth is woody and best removed with a saw. Any stumps will rot quickly if cut at ground level.

Step Four: Install bamboo shield to prevent the bamboo from returning. This is done by digging a trench along the desired controlled area. The Bamboo Shield is then installed in the trench with the shiny side towards the bamboo. It should be angled slightly outward so the bottom is closer and the top is farther away from the bamboo. Leave a 2” lip exposed above ground level.

Step Five: Next, mow or cut any residual bamboo shoots that emerge until the roots have exhausted their stored energy and die. Depending upon the size and maturity of the bamboo, this could take multiple growing seasons.

Step Six: Bamboo is now contained. Since bamboo shield is constructed from High Density Polyethylene, it has a long lifespan. Without exposure to ultraviolet light, the barrier should last in excess of 100 years.

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