February 2002. Papua New Guinea asked whether Aeschynomene americana L. and Indigofera sp. were present in the country. Many members confirmed they were. The question was in connection with a request to import Desmodium intortum (Greenleaf desmodium) into the country. Seeds of A americana L. and Indigofera sp. had been found as contaminants. The request to import also included Vigna parkari (Creeping vigna) to be used in cover crop trials for the oil palm industry.
D. intortum has also been reported to have the potential to become a weed:
Garcia JG, MacBryde ., Molina AR, Herrera-MacBryde O (1975) Prevalent Weeds of Central America. International Plant Protection Centre, El Salvador El Salvador.
Groves RH, Hosking JR (1997) Recent Incursions of weeds to Australia 1971-1995. Technical Series N?? 3. CRC for Weed Management Systems Australia.
Vigna parkeri is a Quarantine weed in Western Australia. It is sold in eastern Australia as a fodder pasture, but assessment deemed it too weedy for introduction into WA. It scored 19 on the Weed RIsk Assessment (WRA) Spreadsheet. More than 6 is a reject. Many legumes need specific innoculants to establish, V parkeri does not: it can use the native rhizobias, allowing it to establish in areas it is not welcome. It is documented as a highly competitive creeper with a number of highly invasive perennial grasses which makes its potential threat significant.
Desmodium intortum is already in Western Australia, but when run through the WRA some time ago scored a 7. It has already naturalised in Queensland and is proving to be an environmental weed there.
Verdcourt (1979) in A Manual of New Guinea Legumes, thinks that Vigna parkeri subsp. maranguensis (Taub.) Verdc. was introduced and grown around Aiyura (EHP) where it spread rapidly throughout agricultural areas.