Erigeron divaricatus Michx. (syn. Conyza ramosissima Cronq.), low fleabane, low conyza, spreading fleabane. Annual, taprooted, not rosetted, 1—several–stemmed at base, with spreading branches, branches not straight, in range 6— < 15 cm tall; shoots typically observed with only cauline leaves, overall appearing grayish green, commonly lacking tufts of leaves from unexpanded axillary shoots, stiff–strigose and short–strigose having appressed white hairs to 1.3 mm long and upward–pointing, the larger hairs with enlarged to swollen, often persistent bases.
Stems finely low–ridged, to 1 mm diameter, tough and wiry, internodes to 5 mm long, with hairs along ridges, lower stem forming periderm and aging glabrescent.
Leaves helically alternate, simple, sessile, without stipules; blade linear (narrowly spatulate), mostly 3—10 × 0.3—0.6 mm (the earliest leaves somewhat longer and wider), entire, acute with reddish or whitish callus at tip, 1–veined with midrib sunken on upper surface and slightly raised on lower surface, strigose.
Inflorescence heads, in terminal, open, cymelike arrays, array never with lower branches overtopping main axis, principal branches with 1—several heads, head obscurely radiate (radiant), at anthesis 1 mm across, in range with 20—30 pistillate peripheral flowers in ca. 2 series and 3—8 bisexual disc flowers, bracteate, strigose; bract subtending lateral branch and peduncle leaflike; peduncle slender with several inconspicuous ridges, at anthesis 1—2 × 0.2—0.25 mm increasing to 10 mm long in fruit, ± strigose; involucre ± cylindric, 3.5—4 × 1 mm with spreading to ascending phyllaries becoming wider in fruit, phyllaries ca. 25, unequal and graduated in 3—4 series, linear, outer phyllaries from 1.2 mm long, green, middle phyllaries with green center and conspicuous white–membranous margins, strigose on green tissues, inner phyllaries mostly white–membranous with only midvein with green border, acuminate at tips, inner phyllaries fringed and rose–colored at tip and glabrous, generally spreading and ca. 7 mm across in fruit; receptacle flat, without bractlets (paleae), not pitted, lacking teeth around each ovary.
Peripheral flower pistillate, bilateral, ca. 0.2 mm across, erect, slightly < inner phyllaries; calyx (pappus) of ca. 30 capillary bristles in 1 whorl, fine, 2—2.6 mm long, whitish aging tawny; corolla minutely 2–lobed or acute at tip, 2.2—2.4 mm long; tube cylindric, to 1.4 mm long, whitish, lacking hairs; limb erect, slender–elliptic, pure white; stamens absent; pistil 1; ovary inferior, ellipsoid bi–convex and compressed side–to–side, 0.4 mm long, colorless, having 2 edges and 2 faces, short–hairy, 1–chambered with 1 ovule; style slightly < tip of limb (corolla), colorless, 2–branched, usually with 1 branch appressed to corolla limb and 1 branch spreading, ca. 0.5 mm long, with upward–pointing short barbs.
Disc flower bisexual, radial, 0.3 mm across, ca. 2.5 mm long; calyx (pappus) of ca. 30 capillary bristles in 1 whorl, fine, 2—2.6 mm long, whitish aging tawny; corolla 4–lobed, ca. 2 mm long; tube + throat 4–sided, greenish white; lobes acute, 0.2.5—0.3 mm long, light yellow; stamens 4, fused to corolla at top of tube, included; filaments ± 0.3 mm long, colorless; anthers fused into cylinder surrounding style, basifixed, dithecal, ± 0.5 mm long, light yellow, with narrow appendages at top, longitudinally dehiscent; pollen white; pistil 1; ovary inferior, ellipsoid compressed side–to–side, 0.4 mm long, colorless, having 2 edges and 2 faces, short–hairy, 1–chambered with 1 ovule; style included, ca. 2 mm long, 2–branched.
Fruits cypselae, monomorphic, with spheroidal array of pappus ca. 7 mm diameter; fruit body ellipsoid compressed side–to–side, 1—1.5 mm long, pale tan with 2 darker edges, short–hairy; pappus of ca. 30 ascending, fine capillary bristles, 2—2.6 mm long. tawny.
A. C. Gibson