Common lambsquarters  (Chenopodium album)

Common lambsquarters, a broadleaf plant, is among the most common summer annuals. It is found throughout California up to an elevation of 5900 feet (1800 m) and inhabits agricultural land and other disturbed areas. Generally common lambsquarters is considered edible. However under certain conditions, plant production of oxalates can increase to levels toxic to livestock when large amounts of leaves are consumed in a short time period. Common lambsquarter is also susceptible to many viruses that affect several crops and ornamentals. These include beet curly top; potato viruses X, M, and S; ringspot viruses of tomato, pepper, potato, Prunus species, and mulberry; and mosaic viruses of alfalfa, bean, beet, barley, lettuce, cucumber, squash, eggplant, hops, primula, watermelon, and wisteria. Many species of small mammals and birds consume the seeds.

Habitat

Fields, pastures, agronomic and vegetable croplands, gardens, orchards, vineyards, landscaped areas, roadsides, and other disturbed locations.

Seedling

The cotyledons and early true leaves are dull bluish green above and often purplish red below. Cotyledons (seed leaves) are narrow, oblong to lance shaped, about 1/6 to 3/5 of an inch (4–15 mm) long, with nearly parallel sides, and stalks that are often purple tinged. The first leaves appear to be opposite to one another along the stem and are almost equal, or somewhat larger than the cotyledons. Leaves are oblong egg shaped to triangular egg shaped and often fold upward along the midvein. Leaf edges are smooth to weakly wavy-toothed and are initially covered with clear, glistening granules that develop into a white powdery coating over time, especially on the lower surface.

Mature plant

Common lambsquarters is an erect plant that can grow up to 5 feet (1.5 m) tall, depending on moisture and soil fertility. Leaves are generally dull and pale gray green, triangular egg shaped to lance shaped, about 2/5 to 2 inches (1–5 cm) long, and have thin stalks that are about half as long as the leaf blade. Lower leaves usually have three main veins that extend from the base that are usually less than 1-1/2 times the width. Leaf surfaces, especially on new growth, are covered with a fine white powdery coating. Stems are single or may have a few rigid, angled branches and are sometimes striated purplish red.

Flowers

Flowers bloom from May through November. Tiny, green, stalkless flowers are packed in dense clusters at the tips of the main stem and branches. The tiny flowers lack petals, and like the leaves, are also covered in a white powdery coating.

Seeds

Seeds are tiny and plants produce two types—smaller black seeds and larger brown ones.

Reproduction

Reproduces by seed.

Related or similar plants

• Nettleleaf goosefoot, Chenopodium murale

More information

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