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Plants of fields, roadsides, thickets, disturbed areas, woodland edges.  Flowers late July through August.  Native..

Biennial.  Taprooted, usually with a single stem, though robust plants may have 2 to 3 stems.  Stems tend to be pubescent toward the base, but become glabrous and glaucous upwards.  Sap is milky white.  Typical height is 3 to 6+ feet.

The overall inflorescence is usually taller than broad, with many ascending to widely spreading, short branches, and many, rather small flower heads.  Flowering branches tend to be located in the upper third of the plant.   

Flower heads are ligulate.  All florets are bisexual and fertile.  Corollas are yellow, varying to yellow-orange.  Involucres are glabrous, initially cylindrical in shape, becoming swollen at base in age (i.e., vase shaped), 10-15 mm tall (in fruit).

Some basal leaves may be present at flowering.  Primary stem leaves are lanceolate, often lobed and toothed, the upper surfaces somewhat lustrous.  Stem leaves tend to become smaller, narrower and unlobed upwards along the stem.

[Notes:  Fernald (1950) recognized several varieties and forms of this species, none of which are recognized by most authorities today.  Forms with unlobed  (but toothed) leaves that are occasionally found, are also referrable to this species.  They are usually similar in flower and fruit to images shown here.]

Cypselae are black, flattened, with 1 to 3 longitudinal nerves and a conspicuous, narrow beak.  Pappus bristles are white.

Similar species:  Lactuca biennis and Lactuca serriola.

For additional information and comparisons with other species, see my article:  Lactuca Additional Information.

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