The Problem with Tamarisk in the
Arkansas River Basin
The lower Arkansas River Basin has become inundated with the encroachment of
Tamarisk (Tamarix sp.), also known as Salt Cedar. Tamarisk is a tenacious
plant that has a deep root system (up to 100 feet) and leaves a salt residue in
the soil.
These characteristics enable it to quickly displace native cottonwoods
and willows as well as adjacent upland plant communities; such as bunch grasses,
sage and rabbit brush. The resulting Tamarisk thickets crowd out streams and
rivers; provide poor habitat for livestock, animals, and birds; increases fire
hazards; and limits human use of the waterways.
While each of these points is
important to one or more constituencies, the single most critical problem is
that Tamarisk steals water by using more water than the native vegetation that
it displaces. This non-beneficial user of the West's limited water resources
dries up springs, wetlands, and riparian areas by lowering water tables.
The benefits of removal and the restoration of the Arkansas River Basin riparian
areas are astonishing. It is estimated that the western United States is losing
from 2 to 4.5 million acre-feet of water per year over what the native plants
would use. This is enough water to supply upwards of 20 million people or to
irrigate over 1,000,000 acres of land. Although Tamarisk is the primary invasive
plant impacting the basin, Russian Olive (Elaeagnus) cohabitate with Tamarisk
and are also important to control in order to restore riparian health.
The Southeastern Colorado Water Conservancy District serves in a leadership
position to oversee the control of non-native invasive tree species throughout
the Arkansas River Basin. Staff members actively participate with the
Tamarisk
Coalition in educating and providing resources to the
public. SECWCD has sponsored numerous educational programs that emphasize the
importance and methods for controlling non-native tree species. Currently, the
District is utilizing GIS mapping techniques to locate and evaluate the amount
of Tamarisk in the Basin. The District establishes partnerships with interested
entities to insure the success of this project and makes efforts to secure
funding sources through matching grants from federal, state, and local monies.