Abstract
Rhododendron ponticum is an invasive species in many countries, including the United Kingdom, Ireland, Belgium, and France. It poses a serious threat to native flora and fauna, as it is capable of altering entire seminatural communities through its vigorous spread. Control is essential if the conservation value of some communities, such as oak woodland and lowland heath, are to be successfully maintained. Commonly used interventions are herbicide application, herbicide application postcut, and cutting (manual or mechanical) alone. Various techniques have been developed to apply these interventions, but often retreatment of the area is required, increasing the cost of control. Here, we evaluate the effectiveness of some commonly used interventions for R. ponticum control using a systematic review methodology. Eleven studies provided data for statistical analysis. Meta-analyses of captured data show that postcut application of the herbicide Glyphosate or applying the herbicides Metsulfuron-methyl or Imazapyr (no cut) can effectively reduce a R. ponticum stand. There is insufficient available experimental evidence for effectiveness of any other intervention. The systematic review process has demonstrated the lack of replicated studies with controls or long-term monitoring and increases the call for more rigorous monitoring of all conservation management interventions. The quality of experimental evidence of the effectiveness of some interventions contrasts with the acceptance of their use through dissemination of experience. The collection and objective review of experience will require active collaboration of organizations concerned with R. ponticum control.
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Acknowledgments
This project was supported by English Nature. We would like to thank John Bacon (EN) and Tony Robinson (EN) for their help in the formulation of the question and Colin Edwards and the Forestry Commission for providing articles. Terry Rowell and Doug Oliver (CCW) have provided valuable information regarding the current clearance methods of R. ponticum. We are grateful for comments on the manuscript from John Bacon (EN), David Burton (EN), Colin Edwards (FC), Keith Kirby (EN), Doug Oliver (CCW) and four referees and for support throughout the review from Zoe Davies.
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Tyler, C., Pullin, A.S. & Stewart, G.B. Effectiveness of Management Interventions to Control Invasion by Rhododendron ponticum. Environmental Management 37, 513–522 (2006). https://doi.org/10.1007/s00267-005-0127-0
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DOI: https://doi.org/10.1007/s00267-005-0127-0