Title

Effects of logging history on invasion of eastern white pine forests by exotic glossy buckthorn (Frangula alnus P. Mill.)

Abstract

The extent to which forests can be invaded by exotic plants and the role of tree harvest in facilitating such invasions are important issues in invasion biology. Our objective was to determine: (a) whether a widespread exotic shrub, glossy buckthorn (Frangula alnus), can invade a common northeastern US forest type, (b) the extent to which logging facilitates buckthorn invasion, (c) whether buckthorn invades gaps through pre-disturbance ('advance') regeneration, (d) whether or not it forms uneven-aged populations in invaded stands. We selected nine eastern white pine - hardwoods stands in Durham, NH. Three were undisturbed, three were clear-cut, and three were partially cut. Cutting occurred >= 6 years prior to sampling. Glossy buckthorn (>= 0.5 m tall) was present in all stands at the time of sampling and most buckthorn populations were all-aged, suggesting that recruitment by seed continued after initial establishment and that long-term persistence in these stands is possible. Buckthorn was present in four of six cut stands prior to cutting, indicating some advance regeneration. The results support the view that forests are not inherently resistant to invasion by exotic plants. Compared to uncut stands, however, buckthorn had higher densities in clear-cut and partially cut stands. In partially cut stands, buckthorn density was greater in canopy gaps than in adjacent uncut areas. Thus, logging facilitated buckthorn invasion. Given this result and the known negative effects of buckthorn on tree regeneration, control measures should be considered when logging stands where buckthorn invasion is likely. (C) 2011 Elsevier B.V. All rights reserved.

Publication Date

2-1-2012

Journal Title

Forest Ecology and Management

Publisher

Elsevier

Digital Object Identifier (DOI)

10.1016/j.foreco.2011.10.035

Scientific Contribution Number

NH00052-M

Document Type

Article

Rights

© 2011 Elsevier B.V. All rights reserved.