Redwood sorrel (Oxalis oregana) is a distinctive perennial plant that often carpets the forest floor in moist, shaded environments. It thrives in coastal redwood and Douglas-fir forests from British Columbia to California, known for its unique foliage and delicate blooms.
Is Redwood Sorrel Edible?
Redwood sorrel is considered edible and has a notable tart, lemony flavor, often described as refreshing. Indigenous American tribes in the Pacific Northwest historically used redwood sorrel in their diets. It is typically consumed in small quantities, valued more for its flavor contribution than as a substantial food source.
Identifying Redwood Sorrel
Accurate identification of redwood sorrel is important before consumption. The plant is recognized by its three heart-shaped leaflets, which resemble clover leaves. These leaflets measure between 1 to 4.5 centimeters and are supported by petioles up to 20 centimeters. A unique feature is their ability to fold downward in response to direct sunlight or touch, a protective mechanism called nyctinasty. The undersides of the leaves may also display a purplish tint.
From spring through fall, redwood sorrel produces delicate, bell-shaped or star-shaped flowers, ranging from white to pinkish-purple. These flowers, approximately 13 to 20 millimeters long, typically feature five petals and five sepals. The plant forms a low-lying groundcover, generally reaching a height of 5 to 20 centimeters, spreading through scaly underground rhizomes. It prefers damp, humus-rich soil and thrives in the shade. While it can be mistaken for common clover, clover’s leaflets are typically round or egg-shaped, whereas redwood sorrel’s are distinctly heart-shaped.
Important Safety Considerations
Redwood sorrel contains oxalic acid, which gives it its characteristic tart taste. While safe in small amounts, consuming large quantities can lead to health concerns. This compound can interfere with calcium absorption and may contribute to kidney stone formation in susceptible individuals. Digestive upset is also a possible outcome of overconsumption.
Individuals with pre-existing conditions such as kidney issues, gout, rheumatism, or arthritis should exercise caution and avoid consuming redwood sorrel. Pregnant individuals are also advised to avoid large amounts. When foraging, accurate identification is important to avoid ingesting toxic look-alikes. While common clover is visually similar, other plants like Hepatica or woodland Anemone species, though having three-lobed leaves, are toxic and should be avoided. Cooking can help reduce the oxalic acid content, and consuming it alongside dairy products may help to chelate some of the oxalic acid.
Culinary Applications and Benefits
With an understanding of safety precautions, redwood sorrel can be a flavorful addition to various dishes. Its bright, lemony flavor makes it suitable as a fresh garnish, adding a zesty accent to salads. It can also be incorporated into pestos, sauces, or soups to introduce a tangy note. Historically, the leaves have been used to create rhubarb-type pies, though a significant quantity of the thin leaf stalks would be required.
Beyond its distinctive taste, redwood sorrel offers nutritional benefits when consumed in moderation. It contains Vitamin C and Vitamin A, along with phytonutrients, fiber, and minerals such as manganese, calcium, potassium, magnesium, copper, and zinc. While it provides these elements, redwood sorrel is typically enjoyed in small quantities for its flavor rather than as a primary source of nutrition.