Putting the Curse on Bamboo

I’ve written here before about how to control bamboo, and kudzu, too. The column was picked up by the Wall Street Journal, and I received mail from all over the country from readers requesting more information. I also received several letters criticizing me for recommending the use of Roundup (glyphosate).
    In recent weeks, there has been a resurgence of requests for information on putting the curse on bamboo. I know I can’t please everyone, but I can tell you how to kill bamboo.
    To control bamboo, you need to know how bamboo grows. During the spring, summer and early fall months, bamboo grows at a very rapid rate with most of the growth occurring above ground. Applying a weed killer during these active-growing months will only result in killing the tops of the plants and not the roots.
    The only effective way to kill bamboo is the kill the roots and rhizomes.
    In mid to late fall, bamboo stops growing, with most of the energy produced by photosynthesis translocating to the roots and rhizomes. Rhizomes are those underground stems with pointed ends that push their way through the soil and send up shoots during spring and summer months. These underground stems grow many feet each year, resulting in the spread of this species. Like the roots, rhizomes are also energy storage organs.
    Therefore, the time to apply a weed killer is in mid to late fall, when all of the energy produced by the foliage through photosynthesis is moving down the stems into the roots and rhizomes.
    Thus to effectively kill bamboo, you want to force the plants to produce as much succulent foliage as possible. This is accomplished by pruning all bamboo stems to the ground in early spring. Hard pruning will force the plants to produce lots of succulent shoots with lots of leaves during the spring and summer. Do not cut or disturb the foliage or the plants until you are ready to spray in mid to late October.
    In mid to late October, select a bright, warm, sunny day and spray glyphosate (Roundup is one of the trade names), at the recommended concentration. Repeat the treatment 10 to 14 days later. The glyphosate will be carried by the sugars down the stem and into the roots and rhizomes.
    Since Monsanto’s patent expired, glyphosate is now manufactured by two companies. If you have a beef against Monsanto, look for an alternate brand to Roundup.
    Allow the plants to remain in place until spring, when you can cut them down. You will no doubt have a few stragglers. Allow these to grow all summer and repeat the treatment as described above.
    If you follow these recommendations, you should have complete control of the bamboo within two years.

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