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African wood-sorrel, Bermuda buttercup, soursob

pink wood-sorrel, world-wide wood-sorrel

Habit Herbs perennial, acaulous, rhizomes present vertical, white, rootlike, stolons absent, bulb usually solitary, sometimes with bulblets at base; bulb scales not observed. Herbs perennial, acaulous, rhizomes and stolons absent, bulblets clustered; bulb scales 3-nerved.
Leaves

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 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.

Inflorescences

umbelliform cymes, 2–12(–20)-flowered;

scapes often becoming fistulose proximally, 15–30 cm, sparsely villous to pilose.

irregular cymes, (3–)8–14(–28)-flowered;

scapes 15–28 cm, moderately villous to glabrate.

Flowers

tristylous in diploids and tetraploids, consistently short-styled in pentaploids;

sepal apices with 2 orange tubercles;

petals deep golden yellow, 15–20 mm.

mostly homostylous, infrequently tristylous;

sepal apices with 2 orange tubercles;

petals violet to lavender or rose purple, 10–16(–20) mm.

Capsules

not seen.

not observed.

2n

= 14, 28, 35.

= 14, 28, rarely 35.

Oxalis pes-caprae

Oxalis debilis

Phenology Flowering Nov–Apr. Flowering Dec–May, rarely again in summer.
Habitat Disturbed areas, orchards, fields, grasslands, oak woodlands, coastal sage, dunes. Fencerows, yards, flower beds, roadsides, disturbed areas, hammock margins, sandy live oak woods, mesic woods, stream and river terraces.
Elevation 10–500 m. [30–1600 ft.] 0–100 m. [0–300 ft.]
Distribution
map from FNA
AZ; CA; s Africa [Introduced in North America; introduced also in West Indies, Bermuda, South America, Europe, Asia (China, Iran, Turkey), n Africa, Australia]
[WildflowerSearch map]
[BONAP county map]
map from FNA
AL; CA; FL; GA; LA; MS; OR; SC; TX; WA; South America [Introduced in North America; introduced also in Mexico, West Indies, Central America, Europe, se Asia (Malesia), Pacific Islands, Australia]
[WildflowerSearch map]
[BONAP county map]
Discussion

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 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.)

Parent taxa Oxalidaceae > Oxalis Oxalidaceae > Oxalis
Sibling taxa
O. albicans, O. articulata, O. bowiei, O. brasiliensis, O. caerulea, O. californica, O. colorea, O. corniculata, O. debilis, O. decaphylla, O. dichondrifolia, O. dillenii, O. drummondii, O. florida, O. frutescens, O. grandis, O. hirta, O. hispidula, O. illinoensis, O. incarnata, O. intermedia, O. latifolia, O. laxa, O. macrantha, O. metcalfei, O. montana, O. oregana, O. pilosa, O. purpurea, O. stricta, O. suksdorfii, O. texana, O. triangularis, O. trilliifolia, O. violacea
O. albicans, O. articulata, O. bowiei, O. brasiliensis, O. caerulea, O. californica, O. colorea, O. corniculata, O. decaphylla, O. dichondrifolia, O. dillenii, O. drummondii, O. florida, O. frutescens, O. grandis, O. hirta, O. hispidula, O. illinoensis, O. incarnata, O. intermedia, O. latifolia, O. laxa, O. macrantha, O. metcalfei, O. montana, O. oregana, O. pes-caprae, O. pilosa, O. purpurea, O. stricta, O. suksdorfii, O. texana, O. triangularis, O. trilliifolia, O. violacea
Synonyms O. cernua Ionoxalis martiana, O. corymbosa, O. debilis subsp. corymbosa, O. debilis var. corymbosa, O. martiana
Name authority Linnaeus: Sp. Pl. 1: 434. (1753) Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 5(fol.): 183; 5(qto.): 236. (1822)
Source FNA vol. 12, p. 146. Treatment author: Guy L. Nesom. FNA vol. 12, p. 152. Treatment author: Guy L. Nesom.
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