Oxalis pes-caprae
Oxalis metcalfei
African wood-sorrel, Bermuda buttercup, soursob
Metcalfe's wood-sorrel
basal, rarely absent at flowering;
petiole 3–12 cm;
leaflets 3, green, rarely mottled with purplish red spots, angular-obcordate, (5–)7–20 mm, lobed 1/4–2/5 length, lobes apically convex, margins and abaxial surface villous, adaxial surface glabrous, oxalate deposits absent.
basal;
petiole 7–15 cm;
leaflets 3, green, obtriangular-obcordate, 11–25 mm, lobed 1/6–1/3 length, lobes apically rounded to shallowly convex, surfaces glabrous, oxalate deposits usually in narrow band 0.5–1.5 mm along margins at base of notch, sometimes evident on one surface but not other, rarely absent.
umbelliform cymes, 2–12(–20)-flowered;
scapes often becoming fistulose proximally, 15–30 cm, sparsely villous to pilose.
umbelliform cymes, 3–7-flowered;
scapes 7–22 cm, glabrous.
tristylous in diploids and tetraploids, consistently short-styled in pentaploids;
sepal apices with 2 orange tubercles;
petals deep golden yellow, 15–20 mm.
tristylous and distylous;
sepal apices with 2 orange, narrow-elongate, nonconfluent tubercles;
petals white to pale green proximally with green veins, purplish to lavender or pink distally, (9–)12–16 mm.
not seen.
cylindric, 6 mm, glabrous.
= 14, 28, 35.
= 28, 42.
Oxalis pes-caprae
Oxalis metcalfei
Outside its native range, Oxalis pes-caprae is mostly represented by a sterile pentaploid morph, although tetraploids also are known. The occurrence of both pentaploid and tetraploid individuals in the exotic range may be the result of independent introductions (P. Michael 1964; R. Ornduff 1986). Fruit production has not been observed in North America, and the plants are assumed to be seed-sterile (Ornduff 1987). Bulbs of O. pes-caprae are rarely collected, as they detach easily from the vertical, rootlike stems. Each bulb may produce over 20, small, whitish bulblets each year. Bulblets may also be formed at the soil surface crown.
Oxalis pes-caprae was reported by J. K. Small (1933) to occur in waste places and cultivated grounds in northern Florida, but as noted by D. B. Ward (2004), no Florida specimens are known.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Oxalis metcalfei has mostly been identified as O. alpina (Rose) Rose ex R. Knuth, but the latter is a species of south-central Mexico, far from the populations in northwestern Mexico and the southwestern United States. Oxalis alpina has leaflets with dotlike oxalate deposits scattered throughout the lamina, concentrated near margins, or as continuous, filiform marginal bands around the lobe apices; the corollas usually are white. Oxalis metcalfei is consistently different in the nature of its foliar oxalate deposits and the corollas usually are purplish to lavender or pink.
Plants with chromosome numbers of 2n = 28 are found in both Arizona and New Mexico; those with 2n = 42 are found only in New Mexico (S. C. Weller and M. F. Denton 1976).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
SW CO Wildflowers
