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.
Fields, pastures, agronomic and vegetable croplands, gardens, orchards, vineyards, landscaped areas, roadsides, and other disturbed locations.
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.
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 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 are tiny and plants produce two types—smaller black seeds and larger brown ones.
Lambsquarter Control Info – Tips For Removing Lambsquarter
Common lambsquarters (Chenopodium album) is an annual broadleaf weed that invades lawns and gardens. It was once grown for its edible leaves, but it is best kept out of the garden because it harbors viral diseases, which can spread to other plants. Keep reading to learn more about how to identify lambsquarters before this weed gets out of control.
How to Identify Lambsquarters
Removing lambsquarter from the lawn and garden effectively is easier once you know how to recognize this weed. The leaves of young lambsquarter seedlings are green with a slight bluish tint on top and reddish purple undersides. The foliage of the youngest seedlings is covered with clear, shiny granules. The granules later turn to a white, powdery coating that is most noticeable on the undersides of the leaves.
Mature leaves are oblong or lancet-shaped, wider near the stem than at the tip, and pale, gray-green in color. They often fold upward along the central vein. The leaf edges are wavy or slightly toothed.
The height of a lambsquarter weed varies from a few inches (8 cm.) to 5 feet (1.5 m.). Most plants have a single central stem, but they may also have a few rigid side stems. The stems often have red striations. Tiny, yellow-green flowers bloom in clusters at the tips of the stems. They usually bloom from July to September, but can bloom early in the season as well.
Lambsquarter weed reproduces only through seeds. Most lambsquarter seeds germinate in late spring or early summer, although they can continue to germinate throughout the growing season. The plants flower in late summer or early fall, and are followed by an abundance of seeds. The average lambsquarter weed plant produces 72,000 seeds that can live in the soil and germinate 20 years or more after they are deposited.
Lambsquarter control in the garden begins with hand pulling and hoeing to remove the weed and mulching. Lambsquarter has a short taproot, so it pulls up easily. The goal is to remove the weed before it matures enough to produce seeds. The plants die with the first frost and next year’s plants grow from the seeds they leave behind.
Consistent mowing to keep lawns at the recommended height will cut down lambsquarter weed before it has a chance to produce seeds. Aerate the lawn if the soil is compacted and minimize foot traffic over the grass to give the lawn a competitive edge over lambsquarter. Maintain a healthy lawn by following a regular schedule of watering and fertilization.
Herbicides also help control lambsquarters. Pre-emergent herbicides, such as Preen, prevent the seeds from germinating. Post-emergent herbicides, such as Trimec, kill the weeds after they germinate. Read the label on the herbicide product of your choice and follow the mixing and timing instructions exactly.