Background
Saltcedar (Tamarix spp.) also known as tamarisk or smoke tree, is a rapidly growing deciduous shrub native to Eurasia and Asia. It was introduced to North America as an ornamental plant in the 1800s. The plant’s pale pink flowers, salt tolerance, and hardiness made it desirable. Those same characteristics contribute to its extreme invasive qualities. Saltcedar has been invading natural habitats in western states, especially in riparian areas where it spreads quickly along the edges of lakes, streams, and rivers. Not only can saltcedar alter natural habitats by impeding stream channels, but it also develops a deep taproot to access groundwater. Once established, saltcedar can utilize 200 gallons of water a day per plant, lowering the water table. High salinity concentrations are left behind in its leaves. Once shed, the salty leaves alter the soil so that other plants cannot survive. This stresses native plants, has little habitat value or benefit for wildlife, and can have detrimental effects on property values.
If saltcedar is planted ornamentally in gardens, it can escape into salt marshes by producing a massive amount of small seedlings that germinate quickly. A mature individual plant (15 to 20 feet tall) can produce 500,000 seeds a year which disperse by wind and water . Saltcedar can also spread aggressively through underground rhizomes.
There are research grade observations of saltcedar on Long Island (Tamarisk parviflora). It is ranked as a Tier II species in New York State, which means that it is a highly invasive species with low abundance in the region. The general management goal is eradication. Due to its ability to survive in cold weather, there is potential that saltcedar can spread across Long Island. Report any observation to LIISMA on iNaturalist app or iMapInvasives. Do not purchase saltcedar or other species in the Tamarix genus. Tamarix ramosissima, Tamarix chinensis, and Tamarix parviflora (smallflower tamarix) are similar in appearance and can hybridize with each other.
When traveling to areas with saltcedar infestations, clean all shoes and gear to prevent spreading seeds to new areas.
Identification
Habit: Shrub or tree 5-20 feet
Leaves: Filamentous needle-like leaves are diamond shaped with a bright green color, alternate and overlapping. Resembles the foliage of cedars (0.5 to 3mm long). Saltcedar has reddish-brown branches that extend vertically.
Flowers: The flowers of saltcedar are small and can be pink or white in color. Horticultural varieties of saltcedar are sometimes sold as pink cascade, summer glow and summer tamarisk.
Habitat
While saltcedar can adapt to a number of environments, it is especially adapted to grow in salty habitats such as along beaches, tidal marshes, and in other tidal wetlands.
Dispersal
Saltcedar seeds can be spread via wind or water and germinate within 24 hours of detecting moisture. Seeds have also been found to germinate while still floating on a river, according to research done in Arizona. Once they’ve reached solid ground, saltcedar can grow one foot per month.
Damage and Impact
Saltcedar’s negative impacts include shading out native plants, blocking aesthetically pleasing views, impeding recreation, and increasing the fire frequency in riparian areas.
Saltcedar is considered a noxious weed and highly invasive plant where it is established in the western United States (California, Arizona, New Mexico, Texas, Colorado, Utah, and Wyoming).
Control
Saltcedar is very difficult to control because it thrives on disturbance. Cutting or burning will only make it resprout more vigorously. Therefore, early detection of this plant is key to protecting Long Island’s native saltmarsh and riparian habitats. Hand pulling of new, young plants has been successful in other regions. For larger infestations, highly targeted herbicide applications may be the most effective option.* Research from New Mexico has found arial treatments using a combination of imazapyr and glyphosate to be effective. As well, cut stump treatments using garlon 4 have been found to eradicate this invasive shrub. Treatment should be conducted once flowers have appeared but before seeds have set to avoid further seed dispersal.
*When considering the use of pesticides, it is your responsibility to fully understand the laws, regulations and best practices required to apply pesticides in a responsible manner. At times, the pest you seek to treat may not be on a pesticide label, requiring a 2ee exemption from NYSDEC. Always thoroughly read the label of any pesticide and consult the NYSDEC or a licensed pesticide applicator with questions. See more information on herbicide use and permitting on our Manage an Invasion page.
Citations
Di Tomaso, J. M. (1998). Impact, Biology, and Ecology of Saltcedar (Tamarix spp.) in the Southwestern United States. Weed Technology, 12(2), 326–336. http://www.jstor.org/stable/3988397
Lovich and Hoddle. Saltcedar. UC Riverside Center for Invasive Species Research. https://cisr.ucr.edu/invasive-species/saltcedar