If you happen to live in a climate that historically doesn’t get much rain, gardening and plant cultivation can become a depressing chore.  Gardeners quickly learn which flowers and vegetables will thrive in their yards and which won’t. Home-owners that aren’t keen on spending time outdoors or doing excessive watering will often plant heat-tolerant or drought-resistant plants. But just because you live in an area prone to drought doesn’t mean any resistant plant will do when it comes to your yard. A non-native plant can turn into an invasive plant and harm the ecosystem.

Bethany Bradley, an ecologist, led a study at the University of Massachusetts Amherst that predicts that warmer temperatures climate change is expected to bring will create a demand for tolerant plants. Countries like Egypt and Saudi Arabia will be more than happy to ship their hardier species into the United States to meet the demand. These plants have the potential to become invasive like kudzu has in the Southeastern United States. Her findings will be posted in February’s online edition of Frontiers in Ecology and the Environment.

"Our study identifies climate change as a risk, which combined with other factors is likely to increase demand for imported heat- and drought-tolerant plants, but this emerging threat is one that policy can effectively address," Bradley says. "The USDA has tools to reduce import risk and we advocate that now is the time put them in place. Pre-import screening has been tested in Australia for about 10 years now and it’s not foolproof, but it seems to have done a good job of separating the really bad import ideas from more benign introductions.”

The study suggests the United States Department of Agriculture nip this problem in the bud by adopting “proactive management practices, in particular pre-emptive screening of nursery stock before new plants are imported, to prevent such an explosion of new invasives.” 

The USDA has the Not Authorized Pending Pest Risk Analysis (NAPPRA) rule, which took effect in the summer of 2011, to try and prevent invasives. The rule requires importers to notify the USDA of plants they would like to bring in so the USDA’s scientists can assess the plant and issue a recommendation to allow or deny the import.

Will the USDA’s NAPRA rule be enough to keep non-native species from entering our eco-systems and threatening our native plants? It should be, but to be safe, plant a rock garden this spring.