Riparian Buffer Establishment Using Various Management Techniques

Bartlett, Stever, Stepenuck, Kris, University of Vermont (2025). Riparian Buffer Establishment Using Various Management Techniques. Technical Report #113, Grand Isle, VT. Lake Champlain Basin Program.

In riparian areas of the northeastern United States, well-established reed canary grass (Phalaris arundinacea) stands are common and have proven to be a challenge for the success of tree plantings during riparian forest restoration projects. To address the opportunity for widespread forest restoration and the challenge of reed canary grass (RCG) infestations, the purpose of this experiment was to assess survival of native trees subject to glyphosate, till and mowing management techniques vs. herbicide-free till and mowing management techniques, and to compare RCG density between plots under caried treatments over time. To accomplish this, treatment plots of ten species of native tree stems were planted at eight sites and stem survival was assessed over two growing seasons. In addition, percent cover of RCG was recorded at each site. Chi Square, independent T-test and binary logistic regression statistics were used to assess tree stem survival and the relationship between tree stem survival and percent cover of RCG between treatment and control plots. The data suggest that preparing plots by tilling and the application of herbicide (glyphosate) combined with two mowing events in each of the two growing seasons did not result in higher tree stem survival rates than the treatment plots that were prepared by tilling only and were mowed four times in each of the two growing seasons. As was expected, plots treated with glyphosate, significantly reduced reed canary grass density in the first growing season. However, after the second growing season the percent cover of RCG in the mechanically treated and chemically treated plots was not statistically different. This suggests that the mechanical prescription was as effective at RCG suppression than the chemical, during the second year. Furthermore, the odds ratio produced by the binary logistic regression models in this study can be useful to practitioners and landowners when considering which methods of management to use in restoration projects.