Oxalis vallicola (Rose) R.Knuth

Mexican Wood-sorrel

Notizbl. Bot. Gart. Berl. 7: 315 (1919), sensu Fl. Victoria 4: 209 (1999) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Naturalised

Herb with stems not evident; bulbs ovoid to globose, 1–1.5 cm long, pointed, tunics creamish or pale brown, vertically ribbed; bulbils formed from old bulbs, sessile. Leaves basal, 3-foliolate; leaflets subsessile, broadly obcordate, 9–35 mm long, 15–53 mm wide, bilobed, green, sometimes with maroon markings, glabrous above, sparsely pubescent below, calli absent, margins sparsely ciliate, sinus < 1/4 to 1/4 of leaflet length, apices rounded, lobes 12–50 mm apart, calli absent; petioles 5–30 cm long, sparsely hairy; stipules conspicuous, to c. 10 mm long, with rounded or obtuse lobes. Inflorescences basal, umbel-like, 6–12-flowered; peduncles longer than leaves, sparsely hairy; pedicels 1–2 cm long, glabrous. Sepals lanceolate, 3.5–5 mm long, glabrous, green with 2 conspicuous orange-brown apical calli. Petals 10–12 mm long, whitish or very pale mauve-pink, pale yellow and green near base. Capsule not developed in Australia. Flowers mainly Dec.–Feb.

*GipP, *HSF, *VVP.

Also naturalised NSW, Tas. Native probably to central America. A rare weed of gardens, roadsides and disturbed areas, known from Melbourne suburbs (Heathmont, Montrose, Sunshine), Somerville, and Ballarat.

The identity of the plants in Australia is unclear, as is the taxonomic status of the species. Denton (1973) treated Oxalis vallicola as a taxonomic synonym of O. latifolia, with no direct reference given to O. vallicola in the discussion. Denton discusses the morphological variation in O. latifolia, but it is unclear whether this encompasses the plants which have been called O. vallicola in Australia. Denton comments that bulbils in O. latifolia are formed either adjacent to the parent bulb or at the tips of 'rhizomes', which is one of the differences used in Australian and New Zealand floras to differentiate O. latifolia and O. vallicola. Denton also gives the corolla colour in O. latifolia as blue, lavender or white, and mentions that the degree of lobing of the leaflets varies from emarginate or barely lobed to deeply lobed. There is no mention of the distinctive fishtail-shaped leaflets, a feature which is usually taken to characterise Australian plants of O. latifolia. It is unclear whether O. vallicola warrants recognition, or whether it is best treated as taxonomic synonym of a variable O. latifolia

Oxalis vallicola is most closely related to O. latifolia, which it resembles in the bulb scale nerves, umbel-like inflorescence, and the absence of calli on the leaflets. But is more like O. debilis in the stylar hairs, and in lacking the fishtail-shaped leaflets. O. debilis differs in having many conspicuous orange-brown calli on the leaf lower surface, more than two calli (up to 5) on at least some sepals, a corymbose inflorescence, and pink flowers. O. vallicola is far less often collected than either O. debilis or O. latifolia.

Created by: Val Stajsic, 2016-09-23
Updated by: Val Stajsic, 2020-03-24

Denton, M.E. (1973). A monograph of Oxalis, section Ionoxalis (Oxalidaceae) in North America, Publication of the Museum - Michigan State University (Biological Series) 4(10): 566-572.

Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Rosanae
order Oxalidales
family Oxalidaceae
genus Oxalis
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <http://avh.chah.org.au>. Find Oxalis vallicola in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Oxalis vallicola in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Victorian Volcanic Plain present naturalised
Gippsland Plain present naturalised
Highlands-Southern Fall present naturalised