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.^[1][2]

Description

Leaves of Oxalis oregana, Redwood sorrel

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.^[3]

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.^[4][5]

Food

The leaves of Oxalis oregana were eaten by Native Americans, probably in small quantities, since they contain mildly toxic oxalic acid, whence the genus name.^[6]

References

1. ^ Burke Museum — WTU Herbarium Image Collection
2. ^ Plant Profile for Oxalis oregana — USDA Plant Database
3. ^ SAPS — Science And Plants for Schools
4. ^ E-Flora BC — Electronic Atlas of the Plants of British Columbia
5. ^ Light interception and utilisation — Plants in Action: Adaptation in Nature, Performance in Cultivation
6. ^ Pojar, Jim; Andy MacKinnon (2004). Plants Of The Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska. Lone Pine Publishing. ISBN 978-1551055305.