Flora of North America species comparison

mostly spreading, without persistent leaf bases, up to 1/2 height or more of plant;

caudex stems absent or spreading in moving sand;

aerial flowering stems spreading, slender, solid, not fistulose, 1.5–4 dm, white-tomentose to thinly floccose, occasionally glabrate and light green.

prostrate or decumbent to spreading or erect, sometimes scapose, rarely absent (Eriogonum), without recurved spines, glabrous or pubescent, sometimes glandular;

nodes not swollen;

tendrils absent;

caudex stems tightly compact to spreading and at or just below the soil surface or spreading to erect and above the soil surface, woody;

aerial flowering stems decumbent to spreading or erect, arising at nodes of caudex branches, at distal nodes of aerial branches, or directly from the root, slender to stout and solid or slightly to distinctly fistulose, rarely disarticulating in ringlike segments (Eriogonum).

cauline, 1 per node, rarely fasciculate, quickly deciduous;

petiole (0.3–)0.5–2 cm, tomentose to floccose;

blade oblong-ovate to round-oblong or orbiculate, (0.3–)0.5–1.5(–3.5) × (0.5–)0.7–1.7(–2) cm, white-tomentose on both surfaces, margins plane, sometimes crisped.

deciduous (persistent in some shrubby and matted Eriogonum species), basal or basal and cauline, rarely only cauline, rosulate, alternate, or infrequently opposite (Goodmania) or in whorls of 3 (Gilmania);

stipules absent (possibly vestigial in some perennial species of Chorizanthe);

petiole present, sometimes indistinct, not articulate or with extrafloral nectaries;

blade simple, rarely lobed (Pterostegia), rarely awn-tipped (Goodmania).

cymose, open, 15–90 × 20–100 cm;

branches dichotomous, white-tomentose to thinly floccose, becoming floccose or glabrate and green;

bracts 3, triangular, 0.5–1.5 mm.

terminal or terminal and axillary, cymose and dichotomously or trichotomously branched, or racemose, simple or compound umbellate, or capitate;

bracts usually connate proximally, leaflike or scalelike, entire apically, sometimes awn-tipped, glabrous or pubescent.

absent or erect, slender, 0.1–0.5 cm, floccose to glabrate.

absent or erect to deflexed relative to inflorescence branch, sometimes reflexed, straight or curved.

1 per node, turbinate-campanulate, 1.5–2.5(–3) × 1.3–1.6(–2) mm, thinly tomentose;

teeth 4, erect, 0.3–0.5 mm.

(2.5–)3–4(–4.5) mm;

perianth greenish yellow to yellow, silky-villous abaxially;

tepals connate proximally, monomorphic, oblong to oblong-obovate;

stamens exserted, 2.5–4 mm;

filaments pilose proximally.

(1–)2–30(–100) per involucral structure, occasionally with stipelike base distal to articulations (Eriogonum);

perianth accrescent in fruit, mostly white to red, yellow, light green, greenish white, maroon, or purple, urceolate to campanulate, occasionally glandular or pustulose abaxially, nearly always minutely glandular along midvein adaxially, glabrous or pubescent;

tepals (5–)6, in 2 whorls of 3, connate proximally, typically not forming tube (except Chorizanthe, Lastarriaea, Mucronea, Pterostegia), petaloid or, rarely, coriaceous (Lastarriaea), monomorphic or dimorphic, entire, emarginate, or lobed to laciniate apically, rarely awn-tipped (Lastarriaea) or apiculate (Eriogonum);

nectary a disk at base of ovary;

stamens 3, 6, or 9 (variously 3–9 in Chorizanthe, Mucronea);

staminodes absent;

filaments usually distinct, occasionally forming staminal tube (Chorizanthe);

pistils 3-carpellate, homostylous;

ovary 1-locular;

ovule 1, orthotropous, placentation basal;

styles 3, distinct;

stigmas capitate.

brown, 3–4(–4.5) mm, glabrous except for scabrellous beak.

brown to black or maroon, homocarpic, winged or unwinged, 3-gonous, less often lenticular or globose-lenticular to globose.

embryo straight or curved.

structures tubular (involucre) or consisting of a series of individual bractlike lobes (involucral bracts) arranged in whorls or spirals, rarely absent (Gilmania), awns present or absent;

involucre cylindric, prismatic, turbinate, campanulate, urceolate, or funnelform with 3–8(–36) usually erect teeth or 4–12 spreading to reflexed lobes (teeth and lobes are distal portions of proximally connate involucral bracts);

involucral bracts in 1–3 whorls, rarely in spirals (Johanneshowellia), free or connate only at base, linear to oblanceolate or ovate.