Japanese dodder (Cuscuta japonica)

Appearance

Cuscuta japonica is an annual, parasitic vine that has recently been introduced into the United States. It is listed as a Federal Noxious Weed.

Foliage

The many-branching stems are fleshy, circular, and pale yellow with red spots and striations. Leaves are minute and scale-like.

Flowers

Flowers are abundant, pale yellow, and sessile.

Fruit

Fruits are capsules that are ovoid and 0.2 in. (5 mm) in diameter. The seeds are brown and grouped with 1 to 3 seeds per capsule.

Ecological Threat

Many species of dodder, some native and some exotic, occur in the United States. Cuscuta japonica parasitizes host plants by penetrating the vascular tissue of the host with structures called haustoria. Severe infestations can kill host plants. It is native to Asia and several infestations have recently been found in Texas, Florida, and South Carolina.