Linum hudsonioides Planch, sand flax. Perennial herb, taprooted, not rosetted, (1—)several–stemmed at base, with ascending to spreading principal branches, in range < 15 cm tall; shoots with only cauline leaves, leaves closely spaced and uniformly ascending, puberulent and faces with evenly spaced, minute, sessile glandular hairs with colorless heads.
Stems 8–ridged, to 1.5 mm diameter, with 3 ridges descending from each leaf, papillate–puberulent along ridges.
Leaves helically alternate, simple and sessile, without stipules; blade triangular and awl–shaped to narrowly ovate, 2.3—7 × 0.7—1 mm, green with membranous margins, entire (not ciliate), acute with fine point at tip, with midrib raised especially at base to keeled, lower surface and margins with minute glandular hairs.
Inflorescence leafy monochasial cyme, terminal, open, several–flowered, bracteate, puberulent and with minute, sessile glandular hairs; branchlets erect to ascending, shootlike with appressed, leaflike bracts to 4 mm long having fine point at tip; pedicel 6–ridged, straight, < 9 mm long, puberulent along ridges and with glandular hairs in furrows.
Flower bisexual, radial, ca. 8 mm across; sepals 5, overlapping and strongly attached to receptacle, tightly appressed to corolla, ovate sharp–pointed at tip, ca. 4.5 × 1.5 mm, green with membranous margins, 3–veined at base, short–fringed to above midpoint on margins; petals 5, widely spreading, fan–shaped, ca. 5 × 3 mm, yellow with red basal portion, easily dislodged; stamens 5, fused ca. 0.3 mm as cup at base of ovary, filaments threadlike, 3 mm long, colorless; anthers exserted, dorsifixed, dithecal, ca. 0.5 mm long, orangish, longitudinally dehiscent; pollen orange; pistil 1, 3.5 mm long; ovary superior, spheric, 1—1.7 mm, greenish, 5–chambered, each chamber with 2 ovules; styles 5 fused to above midpoint, to 3 mm long, yellow–orange, 5–lobed, free portion ca. 1 mm long, muntely papillate; stigma 0.2—0.25 mm diameter, dark green.
Fruit capsule, septicidal and loculicidal, dehiscent by 5 valves, 10–seeded, spheric and scarcely 5–ribbed, in range 2.5—2.7 mm, tan, glabrous.
Seed hemi–ovoid, ca. 2 × 1 mm, glossy, ± orange, minutely textured with collapsed cells, becoming mucilaginous when wetted.
A. C. Gibson