Flora of North America species comparison

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 florida is recognized by its mostly erect stems, thin stems and peduncles (compared to other species), sparsely strigose cauline vestiture of relatively short, slightly curved hairs, rudimentary stipules, and relatively small flowers with petals that usually lack red lines proximally. It is a species primarily of the Atlantic states and Gulf coast, but it also occurs in Arkansas, Louisiana, southwestern Mississippi, Missouri, and Texas, apparently disjunct westward from its main range.

Intermediates between Oxalis florida and O. colorea apparently occur where their ranges come into contact. According to G. Eiten (1963), O. florida intergrades with O. dillenii in forming intermediate homogenous populations as well as hybrid swarms. Eiten treated O. florida as O. dillenii subsp. filipes, but D. B. Ward (2004) noted that the differences between O. florida and O. dillenii are appreciable and intermediates seem few. K. M. Wiegand (1925) observed that O. florida and O. filipes have the appearance of hybrids between O. stricta and either O. dillenii or O. corniculata but that their absence in much of the region where the possible parents both occur argues against this hypothesis.

(Discussion copyrighted by Flora of North America; reprinted with permission.)