The Citrusy Herb That You Can Possibly Forage From Your Own Backyard

Before humans began cultivating crops, they foraged for food. The practice has gained popularity in recent years, with foragers turning their backyards or nearby woodlands into wild supermarkets where they shop for free. Wood sorrel (Oxalis stricta), an invasive weed found throughout most of the United States and Canada, has a tart, citrusy flavor due to the oxalic acid in the plant. The foliage, flowers, and seedpods of the herbaceous perennial are edible and are commonly served raw in salads or brewed for tea. Because it closely resembles another common backyard plant, wood sorrel is sometimes called lemon clover or shamrock plant.

You may find both sorrel and clover in your backyard. While it's also edible, the taste of clover (Trifolium spp.), a plant from the same botanical family, is grassy and sweet, not citrusy. Wood sorrel's smooth or slightly hairy stems grow up to nine inches tall and have small, light green, heart-shaped leaves with a fold along the middle vein. Small yellow flowers with five petals bloom on top of the stalks in the daytime and droop before closing at night. Seed capsules resembling miniature okra develop from the flowers and explode when the tiny seeds are ripe, tossing them into the wind and onto the soil.  Sorrel isn't picky about the type of soil it grows in or the amount of rain or sun it gets.

Nutritional use of wood sorrel goes beyond adding it to salads. Parts of the plant can be used in sauces and syrups, soups, and in baking. Consider adding wood sorrel to your garden for its medicinal properties. Because of its high Vitamin C content, it's been used medicinally to treat an array of ailments including scurvy, sore throat, nausea, and fever. Tea brewed from the leaves is said to soothe mouth ulcers and reduce inflammation. Native Americans of the Kiowa Tribe chewed sorrel to relieve thirst and the Algonquins used it as an aphrodisiac.  The oxalic acid in wood sorrel is a mordant, meaning it fixes color in fabric and can be used as a yellow dye. 

Wood sorrel might be a tasty addition to your dinner table, and the flowers definitely attract pollinators, but it's considered invasive in some areas. It adapts to diverse growing conditions and has a vigorous reproduction cycle that helps it spread quickly. Many horticulturists consider it a problematic ground cover to steer clear of and work to eradicate it, particularly in lawns and turf where hand removal and herbicides are the best ways to get rid of it. Oxalic acid gives the plant its tart flavor, but it also makes it slightly toxic. Most people will not feel ill effects unless they eat large quantities, though people with kidney problems should probably avoid it and horses may develop colic if they eat too much of it. In general, if you're planning to start foraging for food, make sure you can tell the difference between common edible plants and poisonous plants.