Microseris nutans, nodding scorzonella

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Glabrous or slightly scurfy perennial with 1 or several thickened fleshy roots, leafy chiefly toward the base, exceedingly variable, small forms only 1 dm tall, often curved or decumbent, with elongate, very narrow, often laciniate leaves and mostly solitary heads with the involucre only about 1 cm high, passing by continuous variation to erect, robust, branching forms 6 dmm tall, with broader leaves and several larger heads with the involucre as much as 2 cm high; heads nodding in bud, erect at anthesis and after; outer bracts much shorter than the inner, often merely calyculate; flowers matutinal; achenes slightly tapering above, 5-8 mm long, glabrous or puberulent; pappus of 15-20 narrow scales mostly 1-3 (6.5) mm long, each bearing a long, white, plumose terminal bristly often seated between the lobes of the shortly bifid scale; 2n = 18.

Cronquist, A., Holmgren, A.H., Holmgren, N.H., Reveal, J.L., and Holmgren, P.K. (1994) "Intermountain Flora" pg. 428, vol. 5, The New York Botanical Garden New York.