Are All Invasive Species Bad?

This article is explaining  fact that most invasive species are not harmful. Those harmful invasive species makes those that do not have any harmful effect to be considered as harmful. Biologist, Mark Davis, is explaining that newly immigrated invasive species are being automatically attacked giving new arrivals a bad name.

http://www.usnews.com/science/articles/2011/08/31/are-all-invasive-species-bad