8. Arenaria juncea M. Bieberstein, Fl. Taur.-Caucas. 3: 309. 1819.
老牛筋 lao niu jin
Herbs perennial. Roots gray-brown or pale, conic, fleshy. Stems erect, 30--60 cm, hardened, glabrous at base, glandular hairy near cymes, with or without persistent, pale brown, hardened, withered leaves at base. Leaf blade narrowly linear, 1--2.5 cm × ca. 1 mm, 1-veined, base broadened, clasping and sheathing, margin sparsely dentate, shortly ciliate, often involute or flat, apex acuminate. Cymes few to many flowered; bracts ovate, 3--4 × ca. 2 mm, glandular pubescent abaxially, margin broadly membranous, apex acute. Pedicel 1--2 cm, densely glandular villous or glabrous. Sepals 5, ovate, ca. 5 × 2 mm, glabrous or glandular villous abaxially, 1--3-veined, margin broadly membranous, apex acute or acuminate. Petals 5, white, 8--10 mm, elliptic-orbicular or obovate, base shortly clawed, apex obtuse. Stamens 10; filaments ca. 4 mm, those opposite sepals with a gland at base; anthers yellow. Ovary ovoid, ca. 2 mm. Styles 3, ca. 3 mm. Capsule ovoid, equaling or slightly longer than persistent sepals, apex 3-valved; valves 2-cleft at apex. Seeds brown or black, triangular-reniform, tuberculate. Fl. and fr. Jul--Sep.
Open forest margins, mountain grasslands, sandy montane grasslands, low-elevation grassland slopes, steppes, desert steppes, rock crevices; 800--2200 m. Gansu, Hebei, Heilongjiang, Jilin, Liaoning, Nei Mongol, Ningxia, NW Shaanxi, Shanxi [Korea, Mongolia, Russia].
This species is used medicinally.