Sonchus asper habit [Top]
Sonchus asper rosette [Top]
Sonchus asper stem [Top]
Sonchus asper leaf [Top]
Sonchus asper leaf margin [Top]
Sonchus asper inflorescence [Top]
Sonchus asper flower head with fruits [Top]
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Several species of sowthistle (Asteraceae) are common in nurseries and landscapes. The species can overlap the winter and summer annual categories. Seeds germinate in the fall or spring. Seedlings form a rosette of waxy leaves with variable leaf margins. One of the most common species, spiny sowthistle, has prickly leaf margins. In contrast to wild lettuce, sowthistle lacks prickles on the mid-vein of the leaves. In warm weather plants bolt to about 3 to 4 feet tall, but may be shorter. Flowers are bright yellow. Seedhead is similar to dandelion, but smaller. Seeds have a pappus that aids wind and water dispersal. Do not let plants go to seed in the nursery. Well controlled by preemergence broadleaf herbicides available for nursery use. [TOP]