Oxalis montana

Oxalis montana is a species of flowering plant in the family Oxalidaceae known by the common names mountain woodsorrel, wood shamrock, sours and white woodsorrel. It may also be called common woodsorrel, though this name also applies to its close relative, Oxalis acetosella.

This species is a perennial herb native to eastern North America, including eastern Canada and the north-central and eastern United States, and Appalachian Mountains. The Latin specific epithet montana refers to mountains or coming from mountains.

It is very similar to the Eurasian species Oxalis acetosella and has been treated by some botanists as a subspecies of it, O. acetosella subsp. montana (Raf.) Hultén.