The term ‘invasive species’ refers to plants or animals that are currently living in a place in which they are not native. The presence of an invasive species is likely to cause harm to its new environment, economic damage or pose a health risk. Many times invasive species are ill-suited to their new environment and don’t survive. However, some invasive species can flourish because their new environment may lack predators or other methods of population control to keep the new species in check. This allows them to out-compete our native species and can cause an unbalanced ecosystem or even localized extinctions! You may have heard of some of the notorious invasive species in the United States like the gypsy moth, buckthorn, red imported fire ant and the emerald ash borer. Invasive species have become a very common occurrence in North America during the last 20 to 30 years. There has not been a single cause but the increase in interstate transportation and a global economy has accelerated the process. There has been a lot of effort focused on preventing invasive species but the task is so big that it is an ongoing struggle.