Photographer: Jerzy Opioła Source: commons.wikimedia.org Copyright: (CC BY-SA 3.0)
The saltcedar is a spreading plant characterized as a shrub or tree with a height of 5-20 feet. The saltcedar tree is distinguished by petals and sepals arranged in groups of four or five with white to pale-pink coloring. Disagreements within this genus are based on classifications of characters. However, it is believed that approximately eight species of Tamarix are found in the United States.
Saltcedar trees are aggressive plants known for consuming large amounts of water with a recorded amount of 200 gallons per day in Arizona. The amount of water consumed varies with water supply, but this behavior prevents surrounding native plants from receiving necessary amounts of water to sustain life. Saltcedar leaves and stems secrete a high concentration of salt into the ground around them preventing growth and development of native plants. Wildlife is also affected by the saltcedar due to a lack of protein found in the plant rendering it unfit for consumption. Many native birds also find the plant undesirable. According to Anderson and Omhart (1977) the saltcedar only supports four species of birds while native plant species can support 154 species per one hundred acres.
With hundreds to thousands of seeds produced between the months of April and October, the saltcedar tree is able to become established rapidly. Seeds are carried via wind or water and germinate within 24 hours of detecting moisture. In Arizona, a case was reported of seeds germinating while floating on a river. Once grounded, seedlings can grow at an alarming rate of one foot per month during the spring season.
The saltcedar was introduced to the United States in the 1800's as an ornamental plant for landscaping. It reportedly escaped cultivation in the 1870's and was considered a serious threat by the 1920's.
Native Origin: Eurasia
Habitat: As an aggressive habitat generalist the saltcedar is able to grow in conditions of high salinity, submergence, or drought. The saltcedar has been known to replace cottonwoods, willows, and other riparian vegetation from their native habitats.
U.S. Present: All states
Texas: All of Texas
For a map of distribution, survey and eradication efforts click here
Although species classification within this genus are not well understood, two categories have been recognized: the evergreen category (considered non-invasive) and shrubs (considered highly invasive). Within the U.S. only one species in the evergreen category has been recorded, Tamarix aphylla, which does not reproduce sexually within its introduced northern climate. The invasive shrub species found in the U.S. are: Tamarix pentandra, Tamarix tetranda, Tamarix gallica, Tamarix chinensis, Tamarix ramosissima, and Tamarix parvifolia. Some authors only recognize a single invasive species Tamarix pentandra while other others believe hybrid species are present in the U.S.
Mechanical management methods have been shown to be unsuccessful due to the plants ability to re-grow from cuttings or roots alone. However, studies in New Mexico using pesticides such as aerially sprayed imazapyr or imazapyr + glyphosate have been proven effective. In California saltcedar trees have been eradicated by cutting the stump low to the ground and spreading herbicide such as Roundup and Garlon 4 on it.
Anderson, B.W. and R.D Ohmart. 1982. Revegetation for wildlife enhancement along the lower Colorado River. Final report to the U.S. Bureau of Reclamation, Boulder City, Nevada.
Barrows, C.W. 1993. Tamarisk control. II. A success story. Restoration and Management Notes 11: 35-38.
Davenport, D.C., P.E. Martin, and R.M. Hagan. 1982. Evapotranspiration from riparian vegetation: Water relations and irrecoverable losses for saltcedar (Tamarix chinensis). Journal of Soil and Water Conservation 37: 233-236.
Hitchcock, C.L. and A. Cronquist. 1961. Vascular Plants of the Pacific Northwest. Volume 3: Saxifragaceae to Ericaceae. University of Washington Press, Seattle.
Sudbrock, A. 1993. Tamarisk control. I. Fighting Back: An overview of the invasion, and a low-impact way of fighting it. Restoration and Management Notes 11: 31-34.