This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Low undershrubs, with coriaceous narrow entire evergreen leaves, scapose or leafy stems, and rather large heads of both radiate and tubular yellow flowers. Involucre mostly hemispheric, its bracts imbricated in several series, appressed, ovate to lanceolate. Receptacle alveolate. Disk-flowers perfect, their corollas tubular, usually somewhat enlarged upward, deeply 5-toothed. Ray-flowers fertile. Anthers obtuse at the base. Appendages of the style-branches short, lanceolate. Achenes white-villous. Pappus of soft white capillary bristles. [Greek, narrow, referring to the leaves.]
About 18 species, natives of western North America. Type species: Stenotus acaulis Nutt.
Stenotus armerioides Nutt. Trans. Am. Phil. Soc. (II.)
7: 335. 1841. Aplopappus armerioides A. Gray, Syn. Fl. 1: Part. 2, 132. 1884.
Perennial, tufted from a branched woody caudex, glabrous throughout; flowering stems slender, naked above, or quite leafless, 4'-8' high. Basal leaves numerous, narrowly spatulate or linear, acute or acutish, firm, 1-3' long, 1"-2" wide, entire, narrowed below; stem leaves usually 1-3, sessile, linear, sometimes none; head commonly solitary, about I broad; involucre campanulate, 4"-6" high, its bracts broadly oval, green, appressed, obtuse or retuse, scarious-margined, or the inner ovate-oblong and acutish; rays 8-10; achenes canescent or villous; pappus bristles soft, white.
In dry, mostly rocky soil, western Nebraska to Wyoming, Utah and New Mexico. June-July.