The World Flora Online

Herbs, perennial, erect, 20-65 cm tall. Stems 4-angled, usuually glabrous, rarely shortly hairy, hispidulous at nodes, angles thickened. Leaves in whorls of 4, sessile or subsessile; blade drying papery or thinly leathery, linear-lanceolate or lanceolate to ovate, (10-)15-40(-80) × (1-)3-15 mm, glabrous or sparsely puberulent to hispidulous and/or pilose, abaxially never with striate to punctate glandular idioblasts, base cuneate to subrounded, margins usually revolute and antrorsely scaberulous to hispidulous, apex acute or usually narrowly tapered then obtuse to rounded at very tip; principal veins palmate, 3. Inflorescences terminal, elongate or broadly paniculiform, 2-15 cm, with several- to many-flowered cymes in axils of uppermost leaves and terminal; peduncles glabrous or puberulent at nodes, smooth or scaberulous; bracts ligulate, lanceolate, or elliptic, 1-4 mm; pedicels 0.5-2 mm elongating in fruit to 3.5 mm. Ovary subglobose, 0.8-1 mm, glabrous or sparsely to densely strigillose to pilosulous. Corolla white or pale yellow, rotate, 3-4 mm in diam., glabrescent, lobed for 3/4 or more; lobes 4, ovate-lanceolate, acute. Mericarps subglobose, 1-2 mm, pericarp firmly attached but sometimes ± inflated, glabrous or ± densely hairy with ± appressed, ascending, or spreading, straight or curved, but hardly truly uncinate trichomes 0.3-0.5 mm. Fl. May-Aug(-Sep), fr. (May-)Jun-Oct.

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Erect herb, 20-60 cm high. Stems 4-angled, glabrous, 15-40 (-50) x 2-8 (-12) mm, rarely younger branches shortly hairy. Leaves 4 in a whorl, broadly to narrowly lanceolate, obtuse, coriaceous, trinerved, margin and nerves shortly scabrid, otherwise glabrous. Inflorescence of oblong-pyramidal of terminal and axillary cymes, branches divaricate, usually short. Flowers many; pedicels (1-) 2-4 (-6) mm, filiform, glabrous; bracts ovate or elliptic, 2-4 (-6) mm long, Corolla 3-4 mm in diameter, lobes elliptic-lanceolate, subacute, 1.5-2 mm long. Fruit 1.5-2 mm in diameter with white, short appressed and hooked hairs.

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Erect perennial 2–8 dm, the numerous stems commonly short- bearded just beneath the nodes, otherwise glabrous or scaberulous; lvs in 4’s, glabrous or scabrous, lance- linear, 1.5–4.5 cm, 3-nerved, the tip minutely rounded, not mucronate; sterile axillary branches with smaller lvs often developed; fls numerous in terminal, rather showy cymose panicles, with white or slightly creamy cor 3.5–7 mm wide; fr 2 mm, glabrous or with short, straight or curled (not hooked) hairs; 2n=44, 66. In a wide variety of not too dry habitats; circumboreal, s. in Amer. to Del., Ky., Mo. and Calif. June, July.

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10–50 cm hoch. Stängel aufrecht, meist verzweigt, kahl. Mittlere Blätter zu 4 im Quirl, lanzettlich, 1–4 cm lang und 2–8 mm breit, 3nervig, stumpf, Rand wenig umgerollt und von vorwärts gerichteten Stachelchen rau. Blütenstand verzweigt, vie

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6–8. Magerwiesen, Riedwiesen, lichte Wälder, kollin-subalpin. J, A, zerstreut M.

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