Oxalis dillenii.Enrico Romani.Luirig.altervista.org. (Accessed 4/2014).

Oxalis dillenii is a perennial herb 10-40 cm tall, very similar to O. corniculata but not purple tinged, no stolons, taprooted, stems often clustered, erect, eventually kneeling (decumbent); densely fine-hairy, hairs pointed, not septate; stipules to 0.3 cm long, often much smaller. 

Leaves alternate, 3-parted, leaflets 1-2 cm wide, heart-shaped, notched at tip, bright green, somewhat succulent, sour to taste, to 1.4 cm wide, leaf stalk widened at base but not jointed; leaflets folded at midday and during night. 

Flowers yellow, 5- parted, mostly as in O. corniculata; inflorescence more-or-less umbrella-shaped (all flowers in a cluster from one central stalk); main stalk mostly longer than subtending leaves; self-pollinating. 

Fruit stalks strongly bent downward, with capsule held erect (deflexed), capsules 5-ribbed, 1-2.5 cm long, tipped by old stigmas, densely gray-hairy; seeds numerous, brown with white lines along transverse ridges. Dispersal occurs by sudden rupture of the fruit that ejects seeds forcibly from slits in the capsules (Lovett-Doust et al. 1985); Seeds eaten by birds and probably by small rodents (Martin et al. 1951). Attacked by the maize rust fungus Puccinia sorghi and other species of Puccinia (Lovett-Doust et al. 1985). Apparently native to North America. 

Wetland status: UPL. 

Frequency in NYC: Very infrequent. 

Origin: Apparently native to North America. 

Habitat: Weed of gardens and open areas. 

Notes: Edible in small amounts (as with O.corniculata).