A Brief History of Tamarix (Tamarix canariensis)

• Native to Eurasia (stretching from the Mediterranean, through the Mideast, and into China & Japan) and Northern Africa
• Introduced to the U.S. in the early 1800’s
• Invasive behavior was noticed in the late 1800’s
• It has infested over 1 million acres of land in the western U.S. alone
• Large woody shrub to small tree (most species are deciduous)
• Foliage is grey-green or bluish-green in color
• New stems are red, turning reddish brown with age
• Eventually, bark thickens & furrows
• The plant has a similar appearance to dog fennel, especially when it is young. It can also be confused with salt bush and small/sparse-looking cedars.

Identifying Characteristics

• Leaves are scale-like, similar to cedars
• Flowers are pink to pinkish-white
• Leaves are usually encrusted with a fine layer of salt which can be tasted.
• Pinkish plumes of flowers at the ends of the branches are a very distinguishing characteristic

Tamarix Seed Characteristics

• Wind and water dispersed
• Approximately 1mm in size
• Can produce up to 1 million seeds per year per plant
• Require moist soils to germinate
• No dormancy requirement; can germinate in 24 hours if exposed to moisture
• Only viable for 3 to 40 weeks, depending on conditions
• There is a major concern with seeds being spread by equipment moving between sites.

Invasive Characteristics

• Prolific seed producer (can flower the entire growing season)
• Reproduces vegetatively and by seed
• Grows quickly and can produce seed within the first year
• Forms dense monocultures, altering native habitats
• Alters soil chemistry so native plants cannot survive
• When tamarix plants drop their salty leaves in winter, it effectively “salts the earth” and other plants often can’t survive, even after the tamarix has been removed.

Habitat Requirements

• Requires moist soils for 2-4 weeks after germination
• Produces a long tap root to access groundwater
• Grows in a variety of soil types (including sand, loam and clay)
• Needs full sun; shade will hinder their establishment and growth.
• Seedlings do not compete well with other species
• Once seedlings are established, they can compete very well with other species.

An exposed shoreline with slowly receding water is the perfect habitat for tamarix to colonize.
These are the exact conditions created on active Dredge Material Management Area (DMMA) sites. A 20-acre monoculture on Bartram Island was treated in November 2011.

Information provided by:
Jessica Spencer
Biologist, US Army Corps Of Engineers
Invasive Species Management Branch
Office: 904-232-1696
Cell: 904-318-9110
E-mail: jessica.e.spencer@usace.army.mil
November 2012