Greenthread

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Greenthread leaves

Greenthread florets

Greenthread

Greenthread inflorescence

Greenthread

Greenthread leaves

Greenthread

Greenthread

Greenthread head

Greenthread leaf

Greenthread

Morphology

Stem

Erect, 1 to several, simple or branched from base.

Leaves

Numerous, opposite, 2 to 4.5 inches long, 1-3 times pinnately divided; segments linear to filiform, 1/3 to 1 inch long, very narrow, thread-like; upper leaves reduced, not as deeply divided.

Inflorescence

Heads, several to numerous, terminal, on long stalks, urn-shaped, 1 to 1.5 inch wide.

Flower

Bracts of 2 sizes; outer bracts 7-12, narrowly linear, 1/2 as long as inner; inner bracts 8, lanceolate, united to form a cup; tips reddish; ray florets 8, 1/3 to 1 inch long, golden yellow; bases sometimes reddish-tinged; tips 3-lobed; disk florets numerous, corollas reddish brown.

Fruit

Achenes, straight or slightly curved, less than 1/4 inch long, tipped with 2 short, barbed awns, enclosing small seed.

Ecology

Habitat

Dry prairies, roadsides, and disturbed sites, in sandy or gravelly soils.

Distribution

Southeast 1/4 and southwest corner of Kansas.

Additional Notes