Three-nerved sandwort

Arenaria trinervia Linnaeus, Sp. Pl. 1: 423. 1753

Plants annual (or short-lived perennial?), not rhizomatous. Stems prostrate or ascending, branched, angled or grooved, 13-19 cm, retrorsely pubescent in 2 lines. Leaves petiolate; petiole 1-4 mm; blade 3(-7)-veined, ovate to broadly ovate, 5-18 × 4-8 mm, margins ciliate, apex acute. Inflorescences 3-10(-15)-flowered; bracts 1-15 mm, proximal foliaceous, distal much smaller, scarious. Pedicels ascending to erect, recurved in fruit, 4-15(-22) mm. Flowers: sepals 4 or 5, midrib keeled, ovate-lanceolate, 2-4 mm, margins broad, apex acuminate; petals 4 or 5, ca. 1.3 mm, ca. 1/ 2 as long as sepals. Capsules ovoid, 2-2.5 mm, shorter than sepals. Seeds reniform, 1 mm, smooth. 2n = 24 (Europe).

Flowering early summer. Trails in forests; 400 m; introduced; Ohio; Eurasia.

Moehringia trinervia was collected near Cleveland in 1990 on property that formerly was a resort community (R. K. Rabeler and A. W. Cusick 1994). It closely resembles Stellaria media; the multiveined, ciliate leaves, retrorse pubescence in two lines on the stems, broadly scarious sepals, capsules shorter than the sepals, and smooth, appendaged seeds distinguish it from S. media.