Red sorrel  (Rumex acetosella)

Red sorrel is a perennial broadleaf plant found throughout California, except in deserts up to about 9800 feet (3000 m). It inhabits agricultural land and other disturbed areas. Its leaves contain varying levels of compounds called oxalates, which are toxic under certain conditions if ingested in quantity. Because its leaves are sour tasting, livestock generally avoid consuming red sorrel. However, if more palatable forage is unavailable, they may eat it and risk ingesting toxic levels of these compounds.

Habitat

Pastures, grassland, crop fields, orchards, vineyards, roadsides, landscaped areas, nursery crops, gardens, coastal dunes, open disturbed sites in forests and forest plantations and riparian areas.

Seedling

Young cotyledons (seed leaves) are oblong, fused at the base, hairless, dull, and about 1/5 to 2/5 of an inch (5–10 mm) in length. Leaves are stalked, are alternate to one another along the stem, and can change shape over time. The first and next few leaves are egg shaped. Later leaves are arrowhead shaped with basal lobes that spread outward.

Mature plant

One or a few slender stems grow erect from the crown reaching up to 1-1/3 feet (0.4 m) in height. Leaves are hairless and are alternate to one another along the stem, mostly near the base of the plant. Lower leaves are from 4/5 to 4 inches (2–10 cm) long, have stalks that are sometimes longer than the leaves, and develop basal lobes, giving them an arrowhead-shaped appearance. Upper leaves are sometimes linear or lance shaped, and stalked. A characteristic membranous sheath encircles the stem at the base of the leaf. Red sorrel is distinguished from curly dock by its creeping roots, arrowhead-shaped leaves, and the lack of teeth or projections on flower parts that remain attached to the fruit.

Flowers

Flowering takes place from March through November. Small flowers cluster along a branching flower stalk. Initially they are yellowish green, but eventually turn reddish.

Fruits

Reddish brown, granular textured flower parts adhere to the tiny fruit, enclosing it. The fruits are tiny—up to 1/17 of an inch (1.5 mm) long, egg shaped, three sided, glossy, and contain a single seed.

Reproduction

Reproduces from creeping roots and by seed.

Related or similar plants

• Curly dock, Rumex crispus

More information

• Broadleaf ID illustration
• Calflora's distribution map
• For agriculture: UC IPM Pest Management Guidelines