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Japanese Dodder

Domestic Programs Pest Evaluation. Arthur E. Miller, USDA-APHIS-PPQ, AERO, Raleigh, NC. October 6, 2003

Scientific name: Cuscuta japonica Choisy (Cuscutaceae)

Physical description: Dodders are annual holoparasitic vines which attach to and penetrate host plants of diverse families by peg-like haustoria. There are over 150 species world-wide and the species are similar. Vegetative features are of little value in identification. The specimens collected during survey should have flowers and/or seeds present for identification, but should be handled carefully to avoid seed dispersal.

Japanese dodder is a parasitic annual that is rather fleshy and smooth. It may overwinter by seed or established stems on perennials. The stems are circular and much-branched. The stem color is pale yellow with red spots and striations. The leaves are scale-like and about 2 mm long. The numerous flowers are pale-yellow and on very short stalks. The seeds are 2.5 to 3 mm in length and 2 to 3 mm in diameter, variously dented, and range from pale straw to blackish in color.

Origin and North American Distribution: It is native to Asia. Three introductions found some years ago on kudzu apparently have been eradicated in San Antonio, TX, in Quinsy, FL, and at Clemson University, SC. During 2001, it was discovered on several properties in Houston, TX. The hosts there include broadleaf woody species. It has killed an oak tree.

Quarantines: The Federal Noxious Weed List includes Cuscuta spp. other than native or widely distributed species. Dodder seeds are commonly intercepted contaminants of commercial seed shipments entering the United States. Any seed shipment found to contain seed of any dodder is denied entry and the commodity is either devitalized or returned to country of origin. Dodder is also listed in various state noxious weed laws.

Dispersal: Long distance dispersal is by contaminated crop seed. Seed has been found being imported and distributed as a medicinal herb. Dodder seed may be spread to nearby areas by animals, water, equipment, and other means.

Control: Property managers and cooperators may use these strategies:

Cultural Control. Seeds may survive 10 to 20 years in the field. If dodder is widespread in a field, it may be controlled by frequent tillage, flaming, and use of herbicides that kill the dodder plant upon its germination from seed, before the dodder becomes attached to its host.

Hand held burners were used at Clemson for burning as much of the surface seed as possible. The seed pop like popcorn when heated - actually popcorn was used to establish to walking speed. A pre-emergent herbicide was used and the site was converted to lawn.

Chemical Control. The dodder and host plants can be sprayed with a contact herbicide at least twice within 10 days. The infested host plants should be removed and destroyed by burning. The infested sites should be treated with a fumigant and pre-emergent herbicide. Biological Control. No agents are known.

Economic impact: Dodder affects the growth and yield of infested plants. Losses range from slight to complete destruction of the crop in infested. Both woody and herbaceous hosts are attacked. Japanese dodder parasitizes orchard fruits, eggplant, kudzu, potato, pumpkin, purple osier (Salix purpurea), soybean, and tobacco.

Environmental impact: A survey along the coast of Hokkaido, the large northern island of Japan, revealed that Japanese dodder parasitized a total of 32 different species of wild plants belonging to 30 genera of 16 families, as well as 7 crop species.


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USDA Forest ServiceUSDA APHIS PPQ The Bugwood Network University of Georgia Invasive.org is a joint project of
The Bugwood Network, USDA Forest Service & USDA APHIS PPQ.
The University of Georgia - Warnell School of Forest Resources and
College of Agricultural and Environmental Sciences - Dept. of Entomology
Last updated on Wednesday, November 05, 2003 at 01:31 PM
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