December 2010. Samoa would like to know if duckweed (Lemnoideae) is considered invasive. The reason for the interest is its potential as a feed for commercial egg and poultry farms.
There have been records of weediness of some species of Lemna, so it may be advisable to complete an assessment of risk.
The Manager, Information Services, IUCN SSC Invasive Species Specialist Group, Regional Pacific Office, University of Auckland, New Zealand wrote: “Check references 2, 3, 4 and 5 of the aquatic plant profiles on the Global Invasive Species Database that has information on Lemna species but more importantly the weed risk model.”
However, it was said that duckweed is native to Samoa, but very uncommon. It would only become a problem if it were introduced into lakes (e.g. Lake Lanoto’o). It has been found in a small pond at Lefaga, and in the Manono Uta marsh, where it is harmless since there are so many marsh plants to shade it out, and little standing water.