Oxalis debilis
Oxalis macrantha
pink wood-sorrel, world-wide wood-sorrel
Price's wood-sorrel
usually 2–8 from base, erect initially, usually becoming decumbent, 5–20(–40) cm, becoming woody proximally, hirsute-pilose on at least proximal 2/3, hairs curved, loosely and irregularly spreading, nonseptate.
basal;
petiole 10–25 cm;
leaflets 3, green to yellowish green, rounded-obcordate, 17–40(–50) mm, lobed 1/6–1/5 length, lobes apically convex, adaxial surface hirsute, adaxial surface glabrous, oxalate deposits in dots at least around distal margins, often evenly over surface.
basal and cauline;
stipules oblong, margins narrowly flanged or without free portions, apical auricles absent;
petiole 2–7 cm;
leaflets 3, green, obcordate, 3.5–12 mm, lobed 1/5–1/3 length, surfaces usually strigose-hirsute, sometimes glabrate, oxalate deposits absent.
irregular cymes, (3–)8–14(–28)-flowered;
scapes 15–28 cm, moderately villous to glabrate.
umbelliform cymes, less commonly irregular cymes, (1–)3–8-flowered;
peduncles (3–)5–10(–15) cm.
villous, hairs long, spreading.
mostly homostylous, infrequently tristylous;
sepal apices with 2 orange tubercles;
petals violet to lavender or rose purple, 10–16(–20) mm.
distylous, well above level of leaves;
sepal apices without tubercles;
petals yellow to yellow-orange, with prominent red lines proximally, (13–)15–20(–23) mm.
not observed.
angular-cylindric, abruptly tapering to apex, 10–15 mm, sparsely to densely hirsute-pilose, hairs long, sometimes mostly along angles.
brown, transverse ridges usually white.
= 14, 28, rarely 35.
Oxalis debilis
Oxalis macrantha
Oxalis debilis appears to be spreading rapidly in the United States. The species produces numerous bulblets in a basal cluster and apparently also can spread laterally by production of bulblets at the tips of filiform roots or rhizomes; it can form large, dense colonies. A. Lourteig (1980) noted that plants of this species occasionally fruit but consistently reproduce through abundant bulblets. They apparently are seed-sterile in North America.
Oxalis corymbosa and O. debilis were differentiated by A. Lourteig (2000) primarily by the distribution of oxalate deposits in the leaf lamina. In O. debilis, the dotlike deposits are crowded along the margins and absent to distinctly less abundant elsewhere. In O. corymbosa, the deposits are evenly distributed over the whole lamina. In their native range in South America, the two expressions are broadly sympatric and intermediates are common, as they are in the flora area. Intermediates have the oxalate dots along the margins as well as over the whole surface or sometimes mostly on the outer third of the blades, near the margins. There is no justification for formal recognition of two entities.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Oxalis macrantha is restricted mostly to limestone glades in Alabama, Kentucky, and Tennessee. It is recognized by its villous to villous-hirsute stems, flowers in umbelliform cymes, and large yellow to yellow-orange corollas with red lines proximally. The lines in the throat remain visible after drying and usually can be seen on herbarium specimens even from the outside of the flower. A similar pattern also occurs in other species, especially O. grandis, O. illinoensis, and O. texana.
Seemingly disjunct plants of native habitats in Nuevo León, Mexico, identified as Oxalis macrantha apparently are more common than reported by G. L. Nesom (2009b). Whether these are actually disjunct or a parallel morphological expression derived from some Mexican species needs to be investigated.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
OR
CalFlora
Flora NW
LA Plants
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
