Bringing Nature Home: How You Can Sustain Wildlife with Native Plants

by Douglas W. Tallamy

That alien ornamentals are particularly good at outcompeting native vegetation should not come as a surprise. As we’ve seen, the species we import for the ornamental trade are not a random subset of plants that have evolved on other continents but instead are attractive plants selected specifically because they are particularly well defended against insects and pathogens (Tallamy 2004). How many times have you bought a plant that is advertised as being “pest free”? A plant that is “pest free” is inherently unpalatable to insects and often is not susceptible to local diseases. Because such plants do not pass the energy they capture from the sun up the food chain, they do not become functioning members of the ecosystem in which they are planted. What’s more, if one escapes from your garden, it has a competitive edge over native plants that are eaten by a host of native insects and are infected by disease organisms, precisely because it is not burdened by such attacks.