How Climbing Vines at Forest Edges Affect Tree Growth and Mortality in NCR Forests
NPS National Capital Regional Network, Inventory, and Monitoring. Vines are an integral component of forests, competing with trees for resources and influencing forest composition, carbon sequestration, and wildlife resources. Vine abundance is increasing in tropical forests, likely a result of fragmentation and elevated CO2. Research in temperate forests is limited, but studies in the eastern U.S. show a similar increase in abundance. The Inventory and Monitoring Program monitors forests at permanent plots in the Washington, D.C. region. Using these data, we asked: Is abundance of climbing vines increasing? Are vines more likely to spread near forest edges? Does the presence of climbing vines affect tree growth and mortality? We found that: vine abundance is increasing, climbing vines are more likely to spread to trees near forest edges, and tree mortality is greater for trees with climbing vines in their crown. Further, the effect on mortality of vines in the crown was greater for trees near a forest edge.
