Gutierrezia texana (DC.) Torrey & A. Gray var. texana, Texas snakeweed, Texas broomweed, kindling–weed, annual broomweed. Annual, wispy, with photosynthetic branches, taprooted, not rosetted, 1–stemmed at base, erect with ascending branches and upper plant with spreading branches, in range 30—90 cm tall; shoots with widely spaced, short and slender leaves, gland–dotted and resin–coated, somewhat aromatic, not viscid, glabrous.
Stems several–angled or also with furrows, ± 5–sided, < 5 mm diameter at plant base, with 3 inconspicuous ridges descending from each leaf, tough, green, canopy stems mostly 0.5—1 mm diameter and wiry, internodes mostly 35—40 mm long. resin–coated, lower stem lacking leaves when blooming and covered with light brown periderm and flaking epidermis.
Leaves helically alternate, simple, subsessile, without stipules; petiole < 0.5 mm long, if present indistinct from blade, often inconspicuously puberulent on upper side; blade linear, < 5—38 × 0.3—2.2 mm, long–tapered at base, entire or with minute teeth on margins, blunt–acute at tip, 1–veined with midrib sunken on upper surface and raised on lower surface (if wide pinnately veined with 3 veins at midblade), with glandular hairs in sunken pits on both surfaces.
Inflorescence heads, solitary and terminal on canopy shoots, head radiate, 7—12 mm across, in range with (5—)6—8 ray flowers and 8—13 disc flowers, bracteate, glabrous, resinous; bract subtending peduncle leaflike, linear, to 2 mm long; peduncle of head several–ridged, ca. 0.3 mm diameter, with several alternate bracts approaching head (= subtending future peduncles); involucre narrowly inversely conic, at anthesis ca. 1.5 mm diameter spreading in fruit, conspicuously resinous in bud, phyllaries ca. 15 in. 3 series, outer phyllaries 1.5—2 mm long and others to 3 mm long, with wide membranous margins to midpoint, outer phyllaries linear and green above wings, other phyllaries oblong to narrowly obovate with flattish, acute tips; receptacle domed, lacking bractlets (paleae), pitted with a toothed crown surrounding each ovary + minute hairs.
Ray flower pistillate, bilateral, 1—2 mm across; calyx (pappus) of ca. 10 scales in 1—2 series, scales minute (0.1 mm long), translucent and scarious, jagged above midpoint; corolla mostly unlobed or scarcely notched, 4.2—5.8 mm long; tube 0.7—1 mm long, pale to light yellow, channeled on lower side; limb spreading, ovate, 3—4.8 × 1—2.2 mm, light yellow, often with 2 creases on upper surface and short–truncate at tip, after pollination or when stressed coiling under; stamens absent; pistil 1; ovary wedge–shaped compressed top–to–bottom, ca. 0.7 × 0.4 mm, pale green, with resin glands and minute hairs; style exserted from corolla tube, 1—1.2 mm long, 2–branched, branches to 0.5 mm long, divergent, light yellow.
Disc flower bisexual, radial, ± 1.3 mm across; calyx (pappus) of ca. 10 scales in 1—2 series, scales minute (0.1 mm long), translucent and scarious, jagged above midpoint; corolla 5–lobed, 2.3—3 mm long; tube cylindric, 0.7—0.9 × 0.4 mm, pale yellow; throat narrowly bell–shaped, 1.3—1.5 × 0.7 mm, light yellow, glabrous, tube and throat 5–ribbed to sinuses; lobes spreading and not becoming strongly recurved, equal, narrowly ovate, ± 0.4—0.5 mm long, light yellow; stamens 5, fused to corolla at base of throat, to 2 mm long; filaments 0.5 mm long, pale yellow; anthers fused into cylinder surrounding style, included, basifixed, dithecal, 1.5 mm long, yellow, rounded at base, acute at tip, longitudinally dehiscent; pollen yellow; pistil 1; ovary inferior, wedge–shaped, ± 0.7 mm long, with short, ascending hairs, 1–chambered with 1 ovule; style exserted ca. 1 mm, ± 2.5 mm long, 2–branched below midpoint, yellowish below fork, the branches nearly erect (not spreading), conspicuously papillate–hairy.
Fruits cypselae, monomorphic, club–shaped, 1.8—2 × 0.4—0.7 mm, in range purple or mottled purple drying dark brown and light brown, 5–ribbed, cells minute and domed, short–hairy with ascending hairs not obscuring fruit wall; with minute scarious scales surrounding truncate top.
A. C. Gibson