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Plants of fields, roadsides, waste places.  Flowers June to September.  Not native..

Biennial or short-lived perennial.  Taprooted or fibrous-rooted.  Stems are usually solitary, but often many-branched, even from near stem base, and pubescent with short bristles and stiff hairs with hooked tips (see image below).  The sap is milky.  Typical height is 2 to 4 feet.

The overall inflorescence is diffuse and open, usually with a terminal cluster of flower heads, and at least a few ascending to widely-spreading branch inflorescences, each with several flower heads located at branch tips. The terminal cluster often appears umbel-like.

Flower heads are ligulate.  All florets are bisexual and fertile.  Corollas are yellow; 5-toothed, often reddish on the under sides.  The involucral bracts are spreading, with pubescent outer faces!

Basal leaves may be present at flowering.  Stem leaves are lanceolate or oblanceolate, undulate, with clasping bases and irregularly lobed and/or toothed margins; becoming smaller upward.

Cypselae are spindle-shaped, brown, with several ribs that are connected with numerous, minute ridges.  The pappus consists of minutely barbed bristles, fused at base; readily falling.

Similar species:  Picris hieracioides resembles a hawkweed (Hieracium), but is much more widely-branched, and its flower heads are restricted to branch tips.  Sonchus arvensis may be similar in height and flower head size, and often also has an umbel-like, terminal cluster of flower heads, but the branching structure is not as wide and the leaves are flatter, softer, more glabrous and more consistently deeply lobed.   When in flower, Cichorium intybus couldn't be confused with Picris, due to its blue (rather than yellow) flowers.  But, Cichorium also has stiff, widely spreading, largely leafless branches, and can be approximately the same height when fully grown.  So, if a plant is not in flower, it may merit a more careful examination.  Cichorium won't have the hairs with hooked tips.

All-in-all, Picris hieracioides is a brightly-flowered, but rather coarse, stiff, rapidly-spreading weed.

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