Global change global trade, and the next wave of plant invasions


Bradley, B.A., Blumenthal, D.M., Early, R., Grosholz, E.D., Lawler, J.J., Miller, L.P., Sorte, C.J., D'Antonio, C.M., Diez, J.M., Dukes, J.S. and Ibanez, I., 2012. Global change, global trade, and the next wave of plant invasions. Frontiers in Ecology and the Environment, 10(1), pp.20-28. PDF

Summary

Non-natives are constantly arriving to the U.S. via ornamental plant trade, and some go on to become invasive.  Previous studies (such as Van Der Veken et al. 2008) have shown that ornamentals tend to be planted further north and in cooler climates than their native range, suggesting that climate warming could be to their advantage.  But what about new species of ornamental plants being imported? Are they also ‘pre-adapted’ to a warmer climate? Bradley et al. (2012) investigated ornamental plant imports to the U.S. from 2000-2010 and showed that emerging sources of ornamentals — countries with low initial value of plants sent to the U.S., but rapid rises in value over the decade — tended to be in warmer and drier regions of the globe. Shifting consumer demand toward drought- and heat-tolerant species due to climate change could further promote the import of novel plant species. This confluence of supply and demand could create a new wave of non-native plant invasions. 

Take home points

  • The U.S. is importing more ornamental plants from warmer regions of the globe, increasing the likelihood that non-native plants will be ‘pre-adapted’ to a warmer climate

  • Non-natives tend to be warm-adapted, which increases the likelihood that they will do better with climate warming while native species do worse

Management implications

  • Work with the green industry to develop and promote native plants for planting

  • Encourage home-owners to plant native species to benefit native pollinators and reduce the likelihood of invasives (see our summary ‘Why Native’ for more pointers)

Keywords

Novel Introduction Pathways; Review; Invasive Plant; Terrestrial habitat; Risk Assessment