Redwood Sorrel

Oxalis oregana

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. 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.

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