Oxalis debilis Kunth
pink shamrock
Perennial acaulous herb with thick, fleshy, glassy white, contractile root below the main bulb which is surrounded by numerous small bulbils; tunic brown; scales 3-nerved. Lvs 3-foliolate. Petiole usually 7-20 cm long, glabrate or with scattered long hairs; stipular wing broad, membranous, hairy. Petiolule c. 1 mm long, hairy. Lamina of leaflets equal or nearly so, 10-35 × 12-48 mm, broadly obcordate, 2-lobed, rounded, with rather narrow sinus, glabrous or nearly so above, hairy beneath, finely punctate with raised orange calli beneath, especially round the margin. Infl. to 35 cm long, cymose, 3-7- or 10-18-flowered, with long curly hairs; pedicels ± deflexed, very variable in length. Bracts at base of pedicels, 2-3 mm long, with calli present but these often small. Sepals 4-5 mm long, ± elliptic, slightly hairy; calli 2-(4), prominent, orange, apical. Petals 1.5-2 cm long, oblong-obovate, pink to rose, glabrous. Stamens at 2 levels; filaments patently hirsute, dilated towards base, the longer 5-6 mm long. Styles either slightly < the shorter stamens or intermediate between stamen whorls, densely and patently hirsute. Capsule not seen.
N.; S.: widespread.
N. South America and probably C. America and the W. Indies 1958
Primarily a weed of cultivated soil, and waste, usually open, disturbed ground.
FL Nov-May.
O. debilis is generally the commonest of the stemless, bulbil-bearing, pink-flowered oxalis. Dispersal of the numerous small bulbils during cultivation can result in a dense infestation and it is thus regarded as a serious weed in many places. The N.Z. plants have been known as O. corymbosa DC., now treated as O. debilis var. corymbosa (DC.) Lourt. Lourteig has determined N.Z. specimens as this var. and others as the type var. The only significant difference seems to be that var. corymbosa has more fls to the cyme and it is not considered practical to separate them here. There are 2 style morphs in N.Z.: commonest is the mid-style morph, with styles between the 2 stamen whorls, but short-style plants are also often found, with styles slightly < the shorter stamens. The sp. has also been known previously in N.Z. as O. martiana.
