Flora of North America species comparison

green, becoming whitish tan, ± ridged from leaf bases, densely puberulent.

ascending to erect or spreading (greenish when young, with age, bark tan to gray, flaky or fibrous), simple (branched in arrays, sometimes ridged from leaf bases), glabrous, hairy, or stipitate-glandular, sometimes gland-dotted, often resinous.

erect or closely ascending;

sessile;

blades with evident midnerves, linear to oblanceolate or narrowly oblong, 7–30 × 1.5–7 mm, flat to keeled, apices acute (often apiculate), faces glabrous or puberulent, sometimes sparsely stipitate-glandular.

cauline (ascending or spreading, sometimes deflexed, falcate or recurved); alternate; short-petiolate or sessile;

blades with usually evident midnerves plus 0–2 pairs of fainter collateral nerves (secondary nerves raised and reticulate in C. eremobius), filiform, lanceolate, elliptic, or obovate (flat or sulcate, sometimes twisted or folded), margins entire, sometimes hirtellous to ciliate (apices usually acute, sometimes apiculate or spinulose), faces glabrous or hairy, sometimes gland-dotted, often resinous.

obconic, 9–15 × 3–5 mm.

usually turbinate, obconic, or cylindric, sometimes hemispheric, (5–15 ×) 1.5–15 mm.

convex, pitted, epaleate.

0.

5–6;

corollas 7–11 mm, lobes 1–2.1 mm;

style branches 2.4–3.3 mm, appendages 1.5–2 mm.

2–40+ (often 5–6);

corollas yellow, tubes shorter than campanulate to funnelform throats, lobes 5, erect to spreading, triangular to lanceolate;

style-branch appendages mostly attenuate.

20–25 in 4–6 series, in 5 strong vertical ranks, tan, often with green and/or purplish markings, midnerves evident throughout and ± expanded apically, lanceolate to elliptic, 3–8 × 0.5–1.5 mm, unequal, outer often herbaceous, inner scarious, strongly keeled, apices acute to acuminate, flat, faces puberulent.

12–60+ in (2–)3–7 series (in vertical ranks or spirals, tan, sometimes green and/or purplish subapically or along midveins), usually evidently 1-nerved (often keeled, sometimes flat to convex), linear to elliptic, lanceolate to ovate, or obovate to spatulate, unequal, chartaceous, outer sometimes herbaceous, margins scarious (entire, ciliolate to erose, apices acute to acuminate or rounded, sometimes apiculate to cuspidate or cupped), faces glabrous or hairy, often resinous.

in densely cymiform arrays, not overtopped by distal leaves.

discoid (usually short-pedunculate), borne singly or in condensed cymiform clusters, these in usually paniculiform, corymbiform, rarely racemiform arrays.

tan, subcylindric (tapering proximally), ± flattened, 5–6.5 mm, faces glabrous, sparsely glandular distally;

pappi whitish tan, 5.5–7.5 mm.

(tan to reddish brown) turbinate to elliptic or cylindric, sometimes ± flattened to 4–5-angled, often 5–10-ribbed, faces glabrous or densely hairy, sometimes glandular;

pappi persistent, of 15–50+, tan, stramineous, or white, fine to coarse, barbellate, apically attenuate bristles in 1 series (of 12–15, white to stramineous, lanceolate or lance-linear scales in C. stylosus).

= 9.

= 18.