Herbivores consume more nonnative oak leaf material in areas with diverse native plant communities than in less diverse communities. Why diverse plant communities tend to resist invasion by non-native or invasive species remains uncertain. Researchers from the Illinois Natural History Survey and the Morton Arboretum have been examining the potential role of herbivores on the invasion of nonnative plant species in diverse plant communities. The researchers examined herbivore damage on leaves of non-native oak trees in arboreta across the United States. They found that non-native oaks in regions with high oak species diversity showed more leaf damage than those in regions with low diversity.
This article appears in the December 2014 issue of Acres U.S.A.