Oxalis oregana

Oxalis oregana , known as redwood sorrel or Oregon oxalis, is a species of the wood sorrel family, Oxalidaceae, in the genus Oxalis native to moist Douglas-fir and coast redwood forests of western North America from southwestern British Columbia to Washington, Oregon, and California.[1][2]

Oxalis oregana
Oxalis oregana 4988.JPG
Redwood sorrel
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Oxalidales
Family: Oxalidaceae
Genus: Oxalis
O. oregana
Binomial name
Oxalis oregana


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 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] It spreads by a scaly rhizome varying the size of patches they can be seen in throughout moist forest under canopies.[4]

Rapid light responseEdit

Oxalis oregana photosynthesizes at relatively low levels of ambient sunlight (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.[5][6]

As foodEdit

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.[7] They are safe to eat in small amounts for those with no oxalate-related conditions.[8]

Patch of Oxalis oregana. Size can varying dependent on rhizome development.


  1. ^ "WTU Herbarium Image Collection". Burke Museum. Retrieved 2016-05-02.
  2. ^ "Plants Profile for Oxalis oregana (redwood-sorrel)". plants.usda.gov. Retrieved 2016-05-02.
  3. ^ "Nyctinasty and Mimosa leaf movement". Science and Plants for Schools. Retrieved 2016-05-02.
  4. ^ "Burke Herbarium Image Collection". biology.burke.washington.edu. Retrieved 2021-05-01.
  5. ^ "Oxalis oregana". Electronic Atlas of the Plants of British Columbia. Retrieved 2016-05-02.
  6. ^ "12.1.1 Light interception and utilisation". Plants in Action. Archived from the original on 2016-03-19. Retrieved 2016-05-02.
  7. ^ Pojar, Jim; Andy MacKinnon (2004). Plants Of The Pacific Northwest Coast: Washington, Oregon, British Columbia & Alaska. Lone Pine Publishing. ISBN 978-1-55105-530-5.
  8. ^ Benoliel, Doug (2011). Northwest Foraging: The Classic Guide to Edible Plants of the Pacific Northwest (Rev. and updated ed.). Seattle, WA: Skipstone. p. 175. ISBN 978-1-59485-366-1. OCLC 668195076.