Abstract:

Abstract: Through wide investigation and analysis for huge information and document, there are 68 species plants that can be considered for “Chinese important alien invasive and pernicious plants” in Xi’an area. These plants belong to 20 families. 14 are composite. 10 are leguminous plant.10 are grass.30 species of these plants originates from America. Others from Europe, Asia and Africa .Most of the 46 alien plants that had invaded this area are herb. And mainly field weeds. There is one species that is sorted in quarantine plant(darnel).The distribution, ecological environment, extent of injury of these alien invasive plants are studied. The main characters of local invasive plants are discussed. Proper prevention measure is proposed also.