Oxalis pes-caprae |
Oxalis brasiliensis |
|
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African wood-sorrel, Bermuda buttercup, soursob |
Brazilian 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, bulb solitary or clustered, 5–20 × 5–17 mm; outer bulb scales 5–8[–13]-nerved, margins ciliate, inner scales thick, orangish. |
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 often purplish proximally, 3–13[–20] cm, glabrous [sparsely and finely strigose]; leaflets 3, light green, obdeltate with rounded angles, [2–]10–21[–32] mm, lobed 1/10–1/20 length, lobes apically shallowly convex to nearly truncate, margins glabrous or sparsely irregularly ciliate, hairs loose, fine, abaxial surface sparsely but evenly strigose, adaxial surface glabrous, oxalate deposits absent. |
Inflorescences | umbelliform cymes, 2–12(–20)-flowered; scapes often becoming fistulose proximally, 15–30 cm, sparsely villous to pilose. |
umbelliform cymes, 1(–2)[–5]-flowered; scapes 14–17[–30] cm, glabrous. |
Flowers | tristylous in diploids and tetraploids, consistently short-styled in pentaploids; sepal apices with 2 orange tubercles; petals deep golden yellow, 15–20 mm. |
apparently tristylous (mid-styled flowers observed); sepals purplish, apices without tubercles, surfaces glabrous; petals violet-purple, with dark purple veins proximally, 18–20 mm. |
Capsules | not seen. |
narrowly cylindric, 15–22 mm, indumentum not seen. |
2n | = 14, 28, 35. |
|
Oxalis pes-caprae |
Oxalis brasiliensis |
|
Phenology | Flowering Nov–Apr. | Flowering Mar–Jul. |
Habitat | Disturbed areas, orchards, fields, grasslands, oak woodlands, coastal sage, dunes. | Disturbed roadsides. |
Elevation | 10–500 m. (0–1600 ft.) | 30–50 m. (100–200 ft.) |
Distribution |
AZ; CA; s Africa [Introduced in North America; introduced also in West Indies, Bermuda, South America, Europe, Asia (China, Iran, Turkey), n Africa, Australia]
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AL; South America (Argentina, Brazil, Uruguay) [Introduced in North America; introduced also in e Asia (Japan), Australia] |
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 brasiliensis is naturalized in Dallas County (H. E. Horne et al. 2013). The species is recognized by its leaves without oxalate deposits and sepals without tubercles; outer bulb scales with five to eight (to 13) nerves; one or two (or three) flowers per scape; and violet-purple, dark purple-veined corollas. The large, showy flowers make this species popular in the horticultural trade (see http://www.pacificbulbsociety.org/pbswiki/index.php/SouthAmericanOxalis#brasiliensis for additional horticultural information on the species). Growth habit in the Dallas County population ranged from small clumps to dense mats along the roadside, extending to the margin of the woodland. A low percentage of the Dallas County Oxalis brasiliensis population was reproducing by tiny propagules produced at the bract region of the scape. These propagules apparently are highly foreshortened stems, as they produce whorls of small leaves; they do not produce scales and thus are not the so-called aerial bulbils, as in the miniature bulbs described in some South African species (see http://www.pacificbulbsociety.org/pbswiki/index.php/SouthAfricanOxalis). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 146. | FNA vol. 12, p. 153. |
Parent taxa | Oxalidaceae > Oxalis | Oxalidaceae > Oxalis |
Sibling taxa | ||
Synonyms | O. cernua | |
Name authority | Linnaeus: Sp. Pl. 1: 434. (1753) | Loddiges et al. ex Hildebrand: Lebensverh. Oxalis., 43. (1884) |
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