You have probably heard of Kudzu, the invasive species that blankets huge areas of the Southeast in carpets of vines so thick they can starve even mature trees. And, at this time of year, in mid-March, you have probably noticed the hillsides of Central Kentucky coated in what looks like a blanket of snow, but is actually a monotypic horde of Callery pear trees, more commonly known as Bradford pears.
Invasive species can happen when a plant is introduced to an ecosystem it is not native to. Kudzu and Callery pear are both native to Asia, where they are valuable parts of their ecosystems—but in America, they don’t know how to behave, and they grow out of control, replacing biodiverse ecosystems with dense, homogeneous thickets where native species cannot survive.
But will an introduced species always become invasive? Is it possible for an introduced species to benefit the ecosystem?