Galium obtusum Bigelow
Family: Rubiaceae
Galium obtusum image
Morton Arboretum  
Perennial herb with a creeping rhizome 20 cm - 0.8 m tall Leaves: in whorls of four, ascending or loosely spreading, 1 - 3 cm long, 1 - 6 mm wide, linear to lance-shaped to reverse lance-shaped with a rounded tip, one-veined, sometimes slightly rough or roughly hairy along the margins and on the midrib beneath. Inflorescence: a long-stalked, ascending cluster of two to five short-stalked flowers. Flowers: white, 2 - 3.5 mm wide, more or less flat and circular in outline, with four short lobes. Lobes longer than wide, usually pointed. Stamens four, shorter than corolla. Styles two, short. Fruit: dry, indehiscent, 4 - 5 mm wide, spherical, paired, separating when ripe, one-seeded. Stems: matted, slender, four-angled, upright and branched, densely short-bearded at the nodes.

Similar species: No information at this time.

Flowering: mid-May to early August

Habitat and ecology: Occurring in low woods and, more often, in moist meadows. It is also found in moist calcareous habitats and in prairies.

Occurence in the Chicago region: native

Etymology: Galium comes from the Greek word gala, meaning milk, referring to the plants that are used to curdle milk. Obtusum means blunt.

Author: The Morton Arboretum

Matted perennial, strict and branched from the base or diffusely branched throughout, 2-8 dm; stems smooth on the angles but densely short-bearded at the nodes; principal lvs in 4's, linear to lanceolate or oblanceolate, 10-30 נ1-6 mm, obtuse, the margins and the midvein beneath usually ±scabrous or hispid-ciliolate; infls short, almost all terminal, with 3-5 fls on short ascending pedicels, the pedicels in fr 5-10 mm, divaricate, stiff, smooth; fls white, 4-merous, 2-3.5 mm wide, the lobes longer than wide; frs 4-5 mm, ±tuberculate, often only one mericarp developed; 2n=48. Swampy thickets and moist meadows; N.S. and s. Que. to Minn. and S. D., s. to Fla. and Tex. May-July. (G. tinctorium, misapplied) The widespread var. obtusum has the lvs mostly (2)3-5 mm wide, and has consistently bearded nodes. The var. filifolium (Wiegand) Fernald, from s. N.J. to Ga., often near the coast, has lvs mostly 1-2 mm wide, and the nodes are not always bearded.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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