4. Hypericum gentianoides (L.) Britton, Sterns & Poggenb. (pineweed, orange grass)

Sarothra gentianoides L.

Pl. 360 a–c; Map 1564

Plants annuals, with taproots, usually with numerous ascending branches. Stems 8–50 cm long, erect, angled or slightly ridged below each leaf toward the tip, green to light brown, turning orange to orangish brown with age, sometimes peeling in thin strips with age. Leaves not jointed at the base, strongly ascending. Leaf blades 1–4 mm long, 0.5–1.0 mm wide, triangular to ovate, scalelike, rounded to bluntly or less commonly sharply pointed at the tip, truncate or broadly angled at the base, the margins somewhat rolled under at maturity, papery to somewhat leathery in texture, with 1 main vein visible, the surfaces with inconspicuous, minute, yellowish brown to dark green or black resinous dots (usually in a single row on each side of the midvein), the upper surface green, the undersurface green, not glaucous. Inflorescences of mostly solitary flowers in the leaf axils, sometimes with small, loose clusters of 3 or 5 flowers at the branch tips. Flowers actinomorphic. Sepals 5, all more or less similar in size and shape, 1.5–2.5 mm long, not becoming enlarged at fruiting, narrowly lanceolate to narrowly oblong-lanceolate, usually with inconspicuous, minute, yellowish brown to black dots, lines, and/or streaks. Petals 5, 2–4 mm long, narrowly oblong, orangish yellow to yellow, sometimes reddish-tinged, withered and inconspicuous but usually persistent at fruiting. Stamens 5–11, the filaments sometimes irregularly spaced but usually not fused into groups. Ovary 1-locular, with parietal placentation. Styles 3, free above the base, more or less spreading, the stigmas capitate. Fruits 4–7 mm long, at maturity 2–3 times as long as the sepals, narrowly conical to nearly cylindrical, widest near the base, tapered to the persistent styles, triangular in cross-section. Seeds numerous, 0.4–0.8 mm long, the surface with a coarse network of ridges and pits, sometimes appearing longitudinally ribbed, light brown to dark brown. 2n=24. June–September.

Scattered, mostly south of the Missouri River (eastern U.S. and adjacent Canada west to Minnesota and Texas; apparently introduced in South America, Caribbean Islands, and Europe). Glades, upland prairies, ledges and tops of bluffs, openings of dry upland forest, and savannas; also old fields, on acidic substrates.