Biological invasions happen either deliberately or accidentally and are considered as serious threats to the biodiversity and its irreversible impact to the biodiversity is second only to the habitat loss. Thirty common IAS of plants were selected and the study inquired whether the local people were well aware about IAS of flora and if so, whether these species have badly
influenced the environment and farming activities and its distribution in Galigamuwa area.
Primary data were collected through a pretested self-administered questionnaire and 65 households were selected by using Multi stage random sampling technique. Analysis was carried out based on descriptive statistics together with graphical interpretation.