Nature's Water Filter

Giant cane (Arundinaria gigantean) also referred to as rivercane is crucial to restoring ecosystem functioning along the South River. Rivercane is nature’s most effective water filter. Dense growths of the cane called canebrakes provide superb filtering capacity. This vegetation increases soil porosity and enhances infiltration of surface water. This effect is due to the interwoven system of rhizomes, roots, and dense culms which spread out and decreases the speed of stormwater as it flows   across the surface of the ground. As canebrakes are established and become part of the natural habitat the quality of stormwater runoff has been shown to dramatically improve.


The natural functioning of the South River is negatively impacted by soil erosion and sedimentation. During periods of heavy rain, fast moving stormwater runoff scour riverbanks and tear away vegetation that hold the soil in place. Also, runoff laden with sediment from construction sites upstream, has formed a sandy riverbed that constantly shifts depriving aquatic life of adequate protection and making it difficult for favorable habitat to form. Additionally, stormwater runoff contains a variety of contaminants – petrochemicals, herbicides, pet waste, and debris that harm water quality. Urban runoff needs healthy natural environments like rivercane that filter the water and improve water quality.

Rivercane root system

Photo by Thomas R. Peters.

Endangered and Delicate

Across the southeast invasive plants, shrubs, and other vegetation are overtaking the habitat of native vegetation. Invasive Chinese privet was primarily introduced to the U.S. for use as a landscape shrub that grew into a hedge providing privacy, hence the word privet.  Over time, the berries produced by privet were dispersed by birds that ate them for food and stormwater runoff. Chinese privet has overtaken rivercane habitat along the South River and is one of the main reasons for its dramatic decline. Today, rivercane is considered a critically endangered ecosystem because it only covers about two percent of its original area across the southeast.

Rivercane Seeds

Rivercane and privet competition. Photo by Thomas R. Peters.

Photo by Thomas R. Peters.

Rivercane can grow for decades before flowering. When it flowers it dies.

Sometimes the flowering reduces seeds but sometimes not.