Cespitose perennial without rhizomes, erect to decumbent, but scarcely creeping, mostly antrorsely strigose with nonseptate, pointed hairs, the erect part of the stem light greenish, to 4 dm; stipules to 3 mm, or much smaller; lfls 1-2 cm wide; infl umbelliform, the pedicels abruptly divaricate or deflexed at maturity, but with erect frs; pet yellow, 4-10 mm; fr 1.5-2.5 cm, usually grayish-strigose; seeds brownish, conspicuously rugose transversely, the ridges whitish; 2n=18-24. Nearly cosmopolitan weed, often in natural habitats as well, probably originally native to N. Amer. Numerous infraspecific segregates are often defined on the habit and the amount and distribution of the pubescence. (O. filipes; O. florida; O. stricta, misapplied; Xanthoxalis brittoniae; X. colorea)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Ornduff and Denton 1998, Kearney and Peebles 1969, McDougal 1973
Duration: Perennial Nativity: Native Lifeform: Forb/Herb General: Herbaceous perennials, to 20 cm tall, stems unbranching or erect and branching from the base, densely leafy, herbage inconspicuously pubescent with appressed or ascending hairs. Leaves: Palmately compound with 3 wedge-shaped leaflets, these 15-20 mm wide, 5-20 mm long, obcordate at the base, sometimes rounded at the tips, blades on petioles 10-40 mm long, leaflets ciliate to glabrous or nearly so above, usually sparsely strigose beneath. Flowers: Yellow to orange-yellow with 5 clawed petals 3.5-11 mm long, connate at the base, sepals 5, 4-5 mm long and pubescent, stamens 10, filaments united at the base with 5 longer than the others, inflorescences 1-9, flowers borne solitary or in groups of 2-5 on pubescent pedicels 8-10 mm long. Fruits: Fleshy, explosive, cylindrical capsules with 5 cells, 15-30 mm long, 3-4 mm in diameter. Seeds roughly 1 mm long, with a fleshy cover arising from the hilum (a scar on the seed coat). Ecology: Found along streams and in woodlands from 6,000-7,000 ft (1829-2134 m); flowering April-July. Distribution: Throughout most of North America. Notes: Look for this species under Oxalis stricta in older texts. The elevation range for this species is given as 2,500-7,500 (762-2286 m) in older texts. The keys to this species are the yellow flowers, and the erect and lightly pubescent stems with appressed hairs, (stems that are conspicuously pubescent with spreading hairs indicate O. pilosa). Plants in this genus have acidic sap. Ethnobotany: Unknown Etymology: Unknown Synonyms: Oxalis stricta, Oxalis dillenii, Xanthoxalis stricta Editor: LCrumbacher 2011