Scientific Name Synonyms
Russian thistle, prickly Russian thistle
- Salsola tragus is an annual herb that can grow to 4 ft. (1.2 m) tall. It was introduced into the United States in the mid 1870s, possibly as a contaminant in flax seed.
- Leaves are alternate and narrow. Upper leaves have a sharp point at the apex and are 1.3-2 in. (3.3-5.1 cm) long.
- Flowering occurs from midsummer to fall, when small, pink to greenish flowers develop from the leaf axils. Each flower is subtended by 3, spine-tipped leaves.
- Fruits are 0.19-0.31 in. (4.8-7.9 mm) in diameter including the wings. Wings are opaque with smooth margins and veins.
- Ecological Threat
- After Salsola tragus matures it detaches from the root system and tumbles in the wind, spreading seed (like another common name “tumbleweed” suggests). It is native to Eurasia.
- Global Invasive Species Database. 2011. Invasive Species Specialist Group (ISSG) of the IUCN Species Survival Commission
- University of California, Jepson Flora Project
- Flora of North America, www.eFloras.org
- Texas Invasive Plant and Pest Council
- California Invasive Plant Council
- USDA NRCS PLANTS
- USDA ARS GRIN
Images from Bugwood.org