Canyonlands Cottonwood Restoration-Jacob Suter
Channel: Sean Anderson
Date: 2017-07-25

Tamarisk (also known as salt cedar; Tamarix spp.) is a non-native invasive species (NIS). This deciduous shrub/small tree was introduced to our southwestern river corridors and wetlands from Eurasia beginning in the 1800s with eight different species ultimately introduced across the greater United States.  In the southwestern U.S. alone it now dominated more than 647,000 ha (1.6 million ac) of land.

Tamarisk introductions initially came from escapes from ornamental cultivation and later via active plantings for windbreaks and bank stabilization.  Along our riparian corridors Tamarisk forms dense monotypic stands which both exclude/outcompete native riparian vegetation and drawn down the water table to a level that harms much of the rest of our riparian community.  Perhaps the most widely quoted statistic about Tamarisk is that a mature individual can suck up to 760 l (200 gal) of water per day, venting most of that liquid to the atmosphere via evapotranspiration.

Into this challenging situation the National Park Service has decided to start caving out Tamarisk along some small pockets of the Green and Colorado River Corridors beginning in 2010.  Their approach is to use mechanical removal followed by actively planting native cottonwood seedlings and protecting remnant mature individuals.

Ranger Jacob Suter has spearheaded these efforts in Canyonlands National Park.  Here he gives us a quick overview of their efforts at the confluence of the Green and Colorado Rivers.