How to Manage Pests

Identification: Weed Photo Gallery

Catchweed Bedstraw

Scientific name: Galium aparine (Madder Family: Rubiaceae)

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Catchweed bedstraw is a winter or summer annual broadleaf plant. It usually requires a disturbance to establish and is common in gardens, yards, orchards, crop fields, and other disturbed habitats. Although it is a host for some problematic nematode species and overwintering aphids, its flowers provide a food source for some beneficial insects. Because catchweed bedstraw tangles in crops and agricultural equipment, it slows down activities such as harvesting. Its bristles attach to people’s clothing and the hair or wool of animals, aiding in its dispersal. Entanglement in sheep wool reduces value.

Seedling

Cotyledons (seed leaves) are oblong to egg shaped, have slightly notched tips, and are either hairless or have tiny hairs. The cotyledon and stalk combined are about 2/5 to 1-1/5 inches (9–30 mm) long. The stem above the cotyledons is square in cross-section and the first leaf set has two somewhat unequal pairs of leaves.

Mature plant

Stems are square in cross-section, weak, often unbranched, have tiny down-curved prickles (seen under a lens)  Mature plants reach up to 3-1/3 feet (1 m) long. Leaves whorl around the stem in groups of six to eight. Individual leaves have a rounded tip and a tapering base, range from about 3/5 to 1-2/5 inches (14–35 mm) long, have bristled tips, and tiny curved prickles on the leaf edges and midveins that, under a lens, are seen pointing toward the leaf base giving the leaves a raspy or sticky touch.

Flower

Flowers bloom from March through July. Two to nine tiny, greenish to white or yellowish, four-petaled flowers cluster on long stalks from the main stem above the leaf whorls.

Fruit

Fruit have two lobes that are usually densely covered with stiff, hook-tipped hairs and look like pairs of tiny, bristly balls but sometimes are hairless. The fruits are broader than long, about 4/5 to 1/5 of an inch (2–5 mm) wide, and 1/17 to 1/8 of an inch (1.5–3 mm) long. At maturity the two-lobed fruits separate into two nutlets.

Seeds

Nutlets range in shape from nearly round to kidney shaped at maturity.

Reproduction

Reproduce by seed.

Related species/Similar looking plants

Field madder

More information

• Broadleaf ID illustration
• Calflora's distribution map
• See UC IPM's Pest Management Guidelines for agricultural information
• See UC IPM's Catchweed Bedstraw Pest Note for landscape information.