Latin name

Digitaria ciliaris (Retz.) Koel.

Family

Poaceae

Common name(s)

Fingergrass, tropical crab grass, summer grass

Synonym(s)

Digitaris adscendens (Kunth) Henr., D. marginata Link, D. biformis Willd., D. commutata Schultes, Panicum adscendens Kunth, P. ciliare Retz. (basionym), D. sanguinalis var. ciliaris (Retz.) Parl.

Geographical distribution

Asia: China and Korea.

South and Southeast Asia: Bangladesh, Cambodia, India, Indonesia, Lao PDR, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Sri Lanka, Thailand, and Vietnam.

Rest of the world: Costa Rica, El Salvador, Honduras, Italy, Madagascar, Mexico, United Kingdom, United States, and West Africa.

Morphology

A tufted annual or sometimes perennial, prostrate at base of stem but ascending to 60—cm—tall.

Stem: smooth, flattened, ascending, bent, branching and rooting at nodes.

Leaf: alternate, thin with a whitish wrinkled margin, lance-shaped, 5—10—cm—long; bluish green with a white midrib; upper surface has sparse long hairs; prominent membranous ligule with long white hairs.

Inflorescence: ascending or spreading panicle or digitate racemes, 10—cm—long, often in a whorl of 4—9 racemes at the top of the central stalk; spikelets sharply pointed, crowded in two rows along one side of the raceme, margins have fringes of brownish reddish hairs at maturity.

Biology and ecology

Propagated by seeds that have a dormancy period of several months. Germination occurs in the 0—5—mm depth; seeds can be spread in the droppings on soil of livestock.

Weed of dry-seeded rice, upland fields, plantation crops, vegetables, and wasteland.

Agricultural importance

A widespread weed of upland crops. An alternate host of insects such as Nilaparvata lugens (Stål), Chaetocnema basalis (Baly), Dicladispa armigera (Olivier), Leptocorisa oratorius (Fabricius), and Mythimna separata (Walker), stripe and tungro virus diseases, and nematodes Hirschmanniella sp., Meloidogyne sp., Tylenchorhynchus sp., and Pratylenchus spp.

Management

Cultural control: good land preparation and hand weeding and hoeing at the early stage of growth can reduce weed populations.

Chemical control: oxadiazon, butachlor, fenoxaprop, or quinclorac.

Selected references

Catindig JLA, Barrion AT, Litsinger JA. 1994. Developmental biology and host plant range of rice ear-cutting caterpillar Mythimna separata (Walker). Int. Rice Res. Notes 19:23-24.

de Datta SK, Moody K, Sankaran S. 1986. Integrated weed management practices for upland rice. In: Progress in upland rice research. Manila (Philippines): International Rice Research Institute. p 447-460.

Galinato I, Moody K, Piggin. CM. 1999. Upland rice weeds of South and Southeast Asia. Manila (Philippines): International Rice Research Institute. 156 p.

Halfliger E, Schloz H. 1980. Grass weeds 1. Basle (Switzerland): Ciba-Geigy Ltd. 142 p.

Morrill WL, Pena-Elec N, Almazan LP. 1990. Effects of weeds on fecundity and survival of Leptocorisa oratorius (Hemiptera: Alydidae). Environ. Entomol. 19:1469-1472.

Moody K. 1989. Weeds reported in rice in South and Southeast Asia. Manila (Philippines): International Rice Reseach Institute. 442 p.

Moody K, Munroe CE, Lubigan RT, Paller Jr. EC. 1984. Major weeds of the Philippines. Weed Science Society of the Philippines. Laguna (Philippines): University of the Philippines at Los Baños. 328 p.

Pancho JV, Obien R. 1995. Manual of ricefield weeds in the Philippines. Muñoz, Nueva Ecija (Philippines): Philippine Rice Research Institute. 543 p.

Soerjani M, Kostermans AJGH, Tjitrosoepomo G. 1987. Weeds of rice in Indonesia. Jakarta (Indonesia): Balai Pustaka. 716 p.

Contributors

JLA Catindig, RT Lubigan, and DE Johnson