FWNRM Blog

astandofbambooNJL.pngGolden bamboo (Phyllostachys aurea), planted as an ornamental and historically for use as fishing poles, is a familiar sight spreading around old homesteads. Sometimes confused with native river canes (Arundinaria spp.), golden bamboo is one of over a 1000 species of large woody grasses generally referred to as bamboos. With the exception of our native river cane, most species of bamboo are native to Asia, Africa and South America. Bamboos can range in size from short ground covers to timber bamboos such as moso bamboo (Phyllostachys edulis) which can reach heights of over 75 feet and over 5 inches in diameter.

There are two major types of bamboo – clump forming and running. Bamboo stems emerge from a dense rhizomes (underground stems) system which is generally located within the upper 12 inches of soil.  The rhizomes of clumping bamboos have very little horizontal growth before they turn upwards and produce a culm (stem). As a result, they spread fairly slowly. Most clumping bamboos are tropical, not very cold tolerant and generally do not grow well in temperate climates.  In contrast, the rhizomes of running bamboos have significantly more horizontal growth, and can send up multiple culms along the rhizome. Running bamboos tend to be more cold tolerant.

Bamboo has an interesting growth pattern. When culms emerge they elongate very rapidly. Technically this is redistribution of stored carbohydrates from the previous growing season and not new growth from current photosynthesis. Stems do not increase in diameter over time, but remain the same size as when they emerge. Likewise, stems do not increase in height after the first season.  Stems do put on additional branches over time, thereby increasing the amount of leaves available for photosynthesis and growth of the grove. Self-shading will eventually limit this potential increase in photosynthesis.

Is bamboo invasive?  Bamboos flower irregularly, sometimes decades apart. Therefore spread by seed is of minor concern, but can't be completely ruled out.  However, running bamboos will run (up to 15 feet or so a year) and once established are very difficult to control. Golden bamboo and/or several other species of running bamboos are therefore considered invasive by many state invasive plant councils and the University of Florida IFAS assessments (http://assessment.ifas.ufl.edu/).

Once established, bamboo is difficult to control. In open areas, plants can be dug up with heavy equipment as the rhizomes tend to be fairly shallow. Frequent cutting of the entire grove can reduce underground reserves and eventually control the stand. This could take some time depending on the species and on the health and size of the grove. Cut stems can also be treated with herbicides such as glyphosate or imazpyr, but multiple applications are typically required. Foliar sprays may suppress growth but are difficult to apply to mature stands and rarely result in complete control. Granular formulations of imazapyr have been effective but must be used very carefully due to potential non‐target injury of other plants.  In all cases, control is labor intensive.

Several methods are available for containing bamboo rhizome growth: physical barriers, trenching and removal of new shoots. Physical barriers involve burying a strong, non-biodegradable barrier around the perimeter of the grove. Rhizomes will turn and go back the other way when they hit the barrier, although in some cases may grow up and over the barrier. In that case, the rhizome must be cut to prevent spread. Physical barriers typically cost several dollars a linear foot.

Trenching involves digging an open trench to the depth of the rhizomes around the perimeter of the grove. Rhizomes growing into the trench must be cut with clippers or a sharp spade. Trenches should be checked several times a year, especially during the spring and summer expansion period.   

The third approach for containing bamboo growth is removal of new stems which are fragile when first emerging. Once a particular stem is removed, it will not grow back.  Newly emerged stems can be kicked over, mowed or cut with a weed eater.  Multiple removals may be needed depending on how uniformly the new stems emerge, which can vary with species, vigor of the grove and environmental conditions.

There are a few additional concerns with bamboo.  Due to the dense shade and dense leaf little produced by bamboo, little can grow in the understory. Minimal wildlife habitat is provided by bamboo groves.  However, birds are known to roost in bamboo and the fungal lung disease histoplasmosis has been associated with roosting of birds in bamboo.  As a result, it is a good idea to wear a mask when working in bamboo stands.

In summary, bamboo is an intriguing plant but if not contained will grow beyond the area where it is initially planted.  Once established, bamboo is very difficult to control. Caution is required when growing bamboo and consideration of the fate and maintenance of groves into the future must be a consideration.

Note: This article was previously published in an Alabama Treasure Forest Association Newsletter (2015)

Nancy Loewenstein

Extension Specialist
Forestry and Wildlife Sciences
Geographic Area of Responsibility:
Statewide 
Office Address and Contact Information:
3301 Forestry Wildlife Bldg.  
Auburn University, AL 36849  
Show Map 

Mobile:(334) 332-4610
Fax:(334) 844-1084
Specialty Areas:
invasive plants; tree and plant identification

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