Flora of North America species comparison

erect (branched, branchlets relatively many, commonly spreading, threadlike, densely glandular, scabrous to shaggy-hairy).

mostly cauline; alternate;

sessile;

blades linear, margins entire, faces hispidulous and glandular (proximally ± ciliate or shaggy-hairy).

ovoid, 2–4 mm diam.

flat, glabrous, paleate (paleae persistent, in 1 series between rays and discs, connate, forming cups, distinct apices acute, often apiculate).

3–5, pistillate, fertile;

corollas wholly or mostly white (laminae 3-lobed, lobes sometimes each with prominent medial red blotch, overall often fading reddish, sinuses ± equaling laminae).

3–10, bisexual, fertile;

corollas usually wholly white, sometimes lobes each with prominent medial red blotch or reddish overall, tubes shorter than throats, lobes 5, deltate (anthers ± dark purple; styles glabrous proximal to branches).

falling, 3–5 in 1 series (each partly enveloping a ray cypsela, apices acute to attenuate).

radiate, in loose, cymiform arrays.

(rays) ± obcompressed (± 3-angled, abaxial sides usually broadly 2-faced, angles between those faces usually 90+°, adaxial sides nearly flat), apices beaked, beaks off center, faces rugose, glabrous;

or (discs) narrowly clavate, appressed-hairy;

pappi (rays) 0, or (discs) of 4–5 lance-attenuate to aristate scales alternating with 4–5 shorter, ± fimbriate scales.

bracts with tack-glands 0 (strigillose, strongly glandular, margins often proximally pectinate, ciliate).

= 9.