Prickly lettuce is an erect prickly annual growing to 5' tall with alternate, clasping, leaves that are bristly on the undersurface along the mid-vein and irregularly-pinnately toothed.  The stems contain a milky sap, hence the generic name.  The pale yellow ligulate flowering heads are comprised of 14-20 ligules, 5-lobed, on short stems, with involucral bracts imbricated in about 4 series.  The fruit is a light to dark brown, ± rough hairy, lanceolate and beaked achene with 5-7 ribs or veins on each face and a pappus of soft, white, capillary hairs.  Prickly lettuce is an abundant and widespread weed in meadows, woodlands, stream channels and waste places throughout most of California below about 6000', even on the desert, blooming from May to September. It is a native of Europe.

Click here for Latin name derivations: 1) Lactuca 2) serriola.
Pronunciation: lak-TOO-ka ser-ee-OH-la.
Click here for Botanical Term Meanings.