Salt cedar

Tamarix spp.

Background

Identification

• Shrub or small tree, 5 to 20 feet tall.
• Pale green leaves are small and scale-like, on thin stems with many branches.
• Flowers pink to white in color, appearing from spring to late summer.

Identification key in: Hickman, J. ed. 1993. The Jepson Manual: Higher Plants of California. University of California Press.

Habitat and local distribution

• Well-adapted to alkaline soils, wind, and a wide range of temperatures; typically found along waterways.

Impacts

• Excludes other plants from growing underneath, due to salt deposited from leaves.
• Aggressive root system depletes ground water needed by native species.

Prevention and Control

Prevention

• Plant natives or spread native seed in disturbed areas.
• Search threatened areas regularly (at least annually) to look for newly arrived plants.

General control notes

• Difficult to eradicate since species spreads rapidly and usually resprouts after treatment. Follow-up monitoring to treat resprouts essential (Lovich 2000).

Manual or mechanical control

(Lovich 2000)

• Root plowing and cutting—useful for initial removal of heavy infestations; follow-up application of herbicides suggested to treat resprouting.
• Estimated costs: vary depending on if volunteers conduct removal and on the plant density; equipment costs range may from $100 to over $1,000 (Gibbons et al. 1999). There may be additional fees for disposal of plant material.
• Pulling by hand—uprooting of seedlings and small plants.
• Prescribed burning—useful for reducing biomass prior to herbicide application.
• Flooding—effective when thickets can be flooded for one to two years.

Biological control

• Biological control agents—USDA currently testing several insect species from other countries for release in United States (DeLoach 1997).
• Grazing—cattle grazing can reduce amounts of sprout regrowth (Gary 1960).

Chemical control

(Lovich 2000)

• Apply triclopyr (as Pathfinder II®) to bark of smaller stems (< 4-inch diameter); wet bark at base of stem prior to herbicide application.
• Treatment of resprouts by glyphosate (Rodeo® or RoundupPro®) or imazapyr (Arsenal®) during growing season; only Rodeo® is registered for aquatic habitats.
• Estimated costs: costs for materials and application by a contractor are approximately $250 per acre for glyphosate, depending on size of treatment area, scale of treatment, and herbicide dosage. It is recommended to contract a licensed professional for herbicide applications (Gibbons et al. 1999).

Integrated control

• Cut larger shrubs and apply triclopyr (as Garlon 4® or Garlon 3A®); use of Garlon 3A® most effective when applied during growing season (Lovich 2000).

References and more information