- Lactuca serriola is an annual or biennial that can reach heights of 6 ft. (1.8 m).
- Cauline leaves (on the stem) are alternate, 2-14 in. (5-36 cm) long and become smaller up the stem. Leaves have a conspicuous, white midvein with the underside of the vein covered with many prickles.
- In the mid-to-late summer, 0.5 in. (1.3 cm) wide, yellow flowers develop in a branched inflorescence at the apex of the stem.
- Flowers produce dandelion-like seeds.
- Ecological Threat
- Lactuca serriola is native to the Mediterranean region and occurs along roadsides, in abandoned fields, and other disturbed areas. It was accidentally introduced into North America in the late 1890s, possibly as a contaminant in seed.
University of California, Jepson Flora Project 
Ohio Perennial and Biennial Weed Guide 
Virginia Tech Weed Identification Guide 
USGS Weeds in the West Project 
Flora of China, www.eFloras.org 
USDA NRCS PLANTS 
USDA ARS GRIN 
Images from Bugwood.org