Redwood sorrel (Oxalis oregana) is a delicious, sour-sweet herb that grows in redwood forests and similar habitats in California and Oregon.
Its leaves flowers, stems, and roots are all edible and tasty. Its tart flavor is from oxalic acid, which in dietary excess can cause kidney stones. But it’s entirely safe and healthy to eat in moderation, like any other greens.
This plant was gathered to eat by the Kashaya Pomo Indians from February through September.
But before you gather the native redwood sorrel plant, please be mindful of its smaller populations. Instead, I recommend Oxalis pes-caprae (yellow flowers pictured), which is extremely abundant in waste and disturbed areas, lawns, gardens, etc., and is an invasive introduced species.