When the first European settlers set foot in the Americas hundreds of years ago they brought plants and animals from their homeland. Often they brought seeds so that they would be able to grow food. For hundreds of years, people have been introducing new species of plants to the Americas. Often these non-native plants are called “exotics.” Today, a plant that is considered “native” to the Americas is one that was already growing naturally in the area before European settlement. Many of the plants that are seen around the U.S. today are not native in this sense. Exotic plants can also be introduced by migratory birds, animals (through their fecal droppings), and via wind and water.
It should also be noted that exotic species are not limited to plants and can take the form of any non-native wildlife including mammals, insects, fish, etc. — all of which can become invasive species.
In the global society t
oday, you can order plants from around the world to plant in your garden and yard. Most of the non-native plants that have been imported help create a more diverse environment, add to the beauty of the landscape, or provide valuable food. However, some of these non-native plants do not remain confined to your yard. If the new plant is better at survival and reproduction than the native plants in an area, it can take over. When this happens the exotic plant is called an “invasive species” because it invades the new ecosystem and can take over large areas. One reason they may take over is because they may not have any native predators to inhibit their growth. In many cases the invasive species will reduce the diversity of life in an area because it will squeeze out everything else and outcompete for valuable resources such as food and/or water. You can learn more about invasive species at the following resources: