American burnweed

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American burnweed head

American burnweed

American burnweed

American burnweed florets

American burnweed head

American burnweed pappus

American burnweed leaf

American burnweed

American burnweed leaf

American burnweed inflorescence

American burnweed leaves

American burnweed fruiting

American burnweed leaves

Morphology

Stem

1 or 2, erect, glabrous or floccose-tomentose.

Leaves

Basal and cauline, alternate, basal usually withering before flowering, not prickly or spiny, upper gradually reduced; petioles absent or short; blades lanceolate to narrowly ovate, 2 to 8 inches long, 3/5 to 3 inches wide, base wedge-shaped to auricled, margins entire to serrate or weakly pinnately lobed.

Inflorescence

Heads, 2 to 20(-40) in corymb-like arrays; involucres urn-shaped to obconic, .4 to .7 inch; calyculate bractlets 4 to 12; phyllaries usually 21 in 1 series, linear, .4 to .6 inch, tips green, acuminate.

Flower

Ray florets 0; peripheral florets pistillate; corolla white to yellowish white, narrowly tubular 4-5-lobed, 3 outer teeth much longer than 2 inner; disk florets 3 to 100, bisexual, fertile; corolla whitish to yellowish white.

Fruit

Achenes cylindric or tapering slightly to base, 5-angled, 10 to 20-ribbed, 1/10 to 1/8 inch, glabrous or finely pubescent between the nerves; pappus of 60 to 120 white, obscurely barbellate bristles 2/5 to 1/2 inch long.

Ecology

Habitat

Moist woods and thickets, prairie ravines, gardens and flower beds, moist disturbed sites

Distribution

East 1/3 of Kansas, more common in southeast

Additional Notes