Oxalis oregana

Oxalis oregana
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Oxalidales
Family:	Oxalidaceae
Genus:	Oxalis
Species:	O. oregana
Binomial name
Oxalis oregana Nutt.

Oxalis oregana (redwood sorrel, Oregon oxalis) is a species of the wood sorrel family, Oxalidaceae, native to moist Douglas-fir and coast redwood forests of western North America from southwestern British Columbia, Washington, Oregon, and California.

Description

Flowers occur singly; the sepal length is 5–10 mm and that of the petal is 13–20 mm.

Oxalis oregana is a short, herbaceous perennial plant with erect flowering stems 5–15 cm tall. The three leaflets are heart-shaped, 1–4.5 cm long with purplish undersides, on 5–20 cm stalks. The inflorescence is 2.4–4 cm in diameter, white to pink with five petals and sepals. The hairy five-chambered seed capsules are egg-shaped, 7–9 mm long; seeds are almond shaped.

Light response

Redwood sorrel, Oxalis oregana, photosynthesises at relatively low levels of ambient light (1/200th of full sunlight). When direct sunlight strikes the leaves they fold downwards; when shade returns, the leaves reopen. Taking only a few minutes, this movement is observable to the eye.

Food

The leaves of Oxalis oregana were eaten by the Cowlitz, Quileute and Quinault peoples. Like spinach, they contain mildly toxic oxalic acid, which is named after the genus.