Non-native or alien species are often introduced inadvertently for their economic and other uses. They often become invasive and drive away the local species. These species are considered to be second major cause of extinction of species (the first being habitat destruction). Lantana camara has replaced many species in forests of Central India. Parthenium hysterophorus has pushed out several herbs and shrubs from open places in the plains. Water hyacinth (Eichhomia crassipes) was introduced in Indian waters to reduce pollution. It clogged water bodies including wetlands at many places resulting in death of several aquatic plants and animals. Ocimum sanctum (tulsi) is not an invasive species.