The Effects of Integrated Vegetation Management on Richness of Native Compatible Flowering Plants and Abundance of Noncompatible Tree Species on a Right-of-Way in Central Pennsylvania, USA

We examined the effects of integrated vegetation management (IVM) and nonselective mechanical removal techniques (hand cutting and mowing) on the richness and abundance of native compatible flowering plants and noncompatible trees on an electric transmission line right-of-way in central Pennsylvania, USA. Our study focused on native flowering plants to help determine how different vegetation management techniques may affect native wildlife communities. We found no correlation between amount of herbicide applied and native flowering plant species richness or tree abundance. We found that the richness of native flowering plants did not differ between plots treated with an IVM herbicide approach and those that were mechanically treated (t = 1.06, df = 1, p = 0.31). However, mechanically treated plots had significantly higher abundance of trees than IVM plots (t = 3.10, df = 1, p = 0.009). We found that plots that were treated with herbicide mixtures that contained glyphosate in 2012 had lower native flowering plant species richness in 2016 than those treated with herbicide mixtures that did not contain glyphosate (t = -2.44, df = 1, p = 0.04). Our study indicates that long-term IVM approaches support native flowering plant species richness while limiting tree abundance under electric transmission line right-of-way. However, further study is needed to determine if the herbicide type and method (selective versus broadcast) of application affects species richness of native flowering plant communities.