Digitaria ternata(A.Rich.) Stapf 1898

Another species of Digitaria a potential North American invader

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Name: Digitaria ternata (A.Rich.) Stapf 1898
Taxonomic Position:
Metaphyta: Magnoliophyta: Liliopsida: Cyperales: Poaceae
Common Names: Crabgrass; black-seed fingergrass (South Africa)

Digitaria ternata is a widespread, successful crabgrass, and was named in 2001 to the Weed Science Society of America's list of sixteen weeds posing the greatest threat to US ecosystems. Though found in Mexico, this grass is not yet known from the United States or Canada. It is closely related to two species on the Federal Noxious Weed List as per the US Federal Noxious Weed Act of 1974, D. velutina (velvet fingergrass) and D. abyssinica (African couch grass). In all, there are currently thirteen weedy species of Digitaria infesting the United States.

Issues of Concern: The properties that once made crabgrass a desirable crop now make it a harmful weed. A large crabgrass plant is very fecund, producing up to 700 tillers and 150,000 seeds in temperate areas, and even more in tropical regions where it acts as a perennial and flowers all year. While this group of species reproduces by seed, they can root at the nodes to form dense mats in moist soils. Digitaria ternata is a pest of a large variety of crops, including upland rice and cereals, and has the propensity to invade pastures. Therefore, D. ternata has a great potential to be introduced accidentally in agricultural produce from many different sources and have an impact on both crops and natural vegetation.

Pathways: This species could be transported via rice and cereal seeds.

Africa (Angola, Burundi, Cameroon, Ethiopia, Ghana, Guinea, Kenya, Malawi, Mali, Morocco, Mozambique, Namibia, Nigeria, Sierra Leone, Somalia, South Africa, Sudan, Swaziland, Tanzania, Uganda, Zaire, Zambia, Zimbabwe); Asia (China, India, Indonesia, Myanmar, Nepal, Philippines, Thailand); Australia; Europe (Greece); Middle East (Israel, Jordan, Lebanon, Yemen); North America (Mexico); South America (Argentina, Uruguay).

Holm, L.G., Pancho, J.V., Herberger, J.P. and Plucknett, D.L. 1979. A Geographical Atlas of World Weeds. New York, USA: John Wiley and Sons. 391 pp.
Reed, C.F. 1977. Economically Important Foreign Weeds. Potential problems in the United States. Agricultural Handbook No. 498. USDA-ARS-APHIS (p. 67).
Wells, M.J., A.A. Balsinhas, H. Joffe, V.M. Engelbrecht, G. Harding & C.H. Stirton. 1986. A catalogue of problem plants in southern Africa. Memoirs of the Botanical Survey of South Africa 53 (p. 209).

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Warning: The information in this archived item was not confirmed with the appropriate National Plant Protection Organization and is provided solely for informational purposes. Please use this information with caution.