Oxalis debilis
Oxalis pilosa
pink wood-sorrel, world-wide wood-sorrel
hairy western wood-sorrel, hairy wood sorrel
usually 2–8 from base, decumbent to ascending, 10–40 cm, becoming woody proximally, sparsely to densely pilose, hairs spreading irregularly to ± deflexed, nonseptate, longer hairs 0.6–1.2 mm.
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, apical auricles absent;
petiole (1–)2–6 cm, hairs nonseptate;
leaflets 3, glaucous and gray-green to yellowish green, obcordate, 5–12 mm, lobed 1/5–1/3 length, surfaces glabrous to loosely strigose to hirsute-villous, oxalate deposits absent.
irregular cymes, (3–)8–14(–28)-flowered;
scapes 15–28 cm, moderately villous to glabrate.
umbelliform cymes, 1–2(–3)-flowered;
peduncles 1.5–5 cm.
mostly homostylous, infrequently tristylous;
sepal apices with 2 orange tubercles;
petals violet to lavender or rose purple, 10–16(–20) mm.
semihomostylous or distylous, within level of leaves;
sepal apices without tubercles, surfaces strigose to hirsute-strigose;
petals yellow, rarely with red lines proximally, 8–12 mm.
not observed.
angular-cylindric, abruptly tapering to apex, 12–17(–20) mm, strigose-hirsute.
brown to blackish brown, transverse ridges rarely with whitish lines or spots.
= 14, 28, rarely 35.
Oxalis debilis
Oxalis pilosa
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 pilosa has been treated as an infraspecific entity within O. albicans, but the two are sympatric in the southwestern United States and although each is variable, there appear to be relatively few unequivocal intermediates. Reports of O. pilosa from Texas apparently were based on misidentifications of O. albicans and perhaps also of O. dillenii.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
OR
CalFlora
Flora NW
LA Plants
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
