Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Common name(s): [more details]

Chinese: chang hua ma tang

English: Indian crab grass, lesser crabgrass, wire crabgrass

Habit:  grass

Description:  "Annual with slender, widely spreading stoloniferous culms and slender, erect, floriferous culm tips mostly 8-40 cm long.  Scale leaves at base of plant usually densely pubescent.  Sheaths rounded, variously hispid or hirsute to glabrous.  Ligules truncate, erose, mostly 0.3-1 mm long.  Blades variable, mostly 1-4 cm long and 1-3 mm wide but the lower ones to 8 cm long and 5 mm wide, typically with long, stiff, often papilla-based hairs scattered on both surfaces but occasionally glabrous.  Inflorescence of 2, occasionally 3, slender branches 2-7 cm long on a long, filiform peduncle.  Spikelets mostly 1.3-1.7 mm long, in pairs along the midrib of a broadly winged rhachis.  Both spikelets of the pair similar and pedicelled but the pedicels unequal in length.  First Glume typically absent but occasionally at least vestigial.  Second glume about as long as spikelet, pubescent on margins with 5 more or less equidistant nerves.  Lemma of lower floret as long as spikelet, pubescent on margins at least near apex, with 7 more or less equidistant nerves.   Lemma and palea of upper floret light-coloured, usually grayish" (Dassanayake, 1994; p. 167).

Description from GrassBase.

Habitat/ecology:  "[M]ost common in light textured soils...along roadsides and in waste areas.  In southeast Asia, found from sea level to 1200 m.  It survives in open scrub, deciduous forests and bamboo forests and on rice bunds in Asia" "[M]ost common in light textured soils...along roadsides and in waste areas.  In southeast Asia, found from sea level to 1200 m.  It survives in open scrub, deciduous forests and bamboo forests and on rice bunds in Asia" (Holm et al., 1997; pp. 301-302).  In Sri Lanka, "a common grass of open, moist field borders, roadsides, and pasturelands at low to medium elevations" (Dassanayake, 1994; p. 167).  In Sri Lanka, "a common grass of open, moist field borders, roadsides, and pasturelands at low to medium elevations" (Dassanayake, 1994; p. 167).

Propagation:  Seed, spread by wind, water and animals (Holm et al., 1997; p. 302).

Native range:  "Native throughout the Old World tropics and introduced into the New World tropics and subtropics" (Dassanayake, 1994; p. 167).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Federated States of Micronesia Chuuk Islands	Dublon (Tonowas) Island	native	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 38)
Federated States of Micronesia Chuuk Islands	Weno (Moen) Island	native	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 38)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	native	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 38)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island		Glassman, S. F. (1952) (p. 127)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	native	Herrera, Katherine/Lorence, David H./Flynn, Timothy/Balick, Michael J. (2010) (p. 56) Voucher cited: T. Hosokawa 5875 (BISH)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced	Wester, Lyndon (1992) (p. 121)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced	Wester, Lyndon (1992) (p. 121)
Philippines Philippine Islands	Philippine Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia Australia (continental)	Australia (continental)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Australia Australia (continental)	Northern Territory		Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 301)
Australia Australia (continental)	Queensland		Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 301)
Cambodia Cambodia	Cambodia (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	China (People's Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	Hong Kong	native	Wu, Te-lin (2001) (p. 332) On farmlands.
Indonesia Indonesia	Indonesia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Malaysia Malaysia	Malaysia (country of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Singapore Singapore	Singapore (Republic of)	native	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 34) Common
Taiwan Taiwan	Taiwan Island	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Thailand Thailand	Thailand (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Vietnam Vietnam	Vietnam (Socialist Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
British Indian Ocean Territory Chagos Archipelago	Diego Garcia Island	introduced invasive	Topp, J. M. W. (1988) (p. 17)
British Indian Ocean Territory Chagos Archipelago	Diego Garcia Island	introduced invasive	Rivers, Julie (2004) (p. 2)

Additional information:
Additional online information about Digitaria longiflora is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Digitaria longiflora as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Digitaria longiflora may be available from the Germplasm Resources Information Network (GRIN).

References:

Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species. Raffles Museum of Biodiversity Research, National University of Singapore. 273 pp.

Dassanayake, M. D., gen. ed. 1994. A revised handbook to the flora of Ceylon. Vol VIII. Amerind Pub. Co., New Delhi. 458 pp.

Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce. 1987. A geographical checklist of the Micronesian monocotyledonae. Micronesica 20:1-126.

Glassman, S. F. 1952. The flora of Ponape. Bishop Mus. Bull. 209: 1-152.

Herrera, Katherine/Lorence, David H./Flynn, Timothy/Balick, Michael J. 2010. Checklist of the vascular plants of Pohnpei with local names and uses. Allertonia, in press. National Tropical Botanical Garden, Lawai, Hawai‘i. 146 pp.

Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James. 1997. World weeds: natural histories and distribution. John Wiley & Sons. 1129 pp.

Rivers, Julie. 2004. Botanical survey update of Diego Garcia, Chagos Archipeligo, British Indian Ocean Territory. Naval Facilities Engineering Command, Pacific. 16 pp. plus "List of the higher plants of Diego Garcia".

Topp, J. M. W. 1988. An annotated check list of the flora of Diego Garcia, British Ocean Territory. Atoll Research Bulletin No. 313. Smithsonian Institution, Washington. 21 pp.

U.S. Dept. Agr., Agr. Res. Serv. 2011. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Wester, Lyndon. 1992. Origin and distribution of adventive flowering plants in Hawai‘i. In: Stone, Charles P.; Smith, Clifford W. and Tunison, J. Timothy. Alien plant invasions in native ecosystems of Hawaii: Management and Research. University of Hawaii, Cooperative National Park Research Studies Unit, Honolulu. University of Hawaii Press. .

Wu, Te-lin. 2001. Check List of Hong Kong Plants. Hong Kong Herbarium and the South China Institute of Botany. Agriculture, Fisheries and Conservation Department Bulletin 1 (revised). 384 pp.

Zhengyi, Wu/Raven, Peter H./Deyuan, Hong. 2011. Flora of China (online resource).