Overstorey tree species regulate colonization by native and exotic plants: a source of positive relationships between understorey diversity and invasibility

Abstract

The North American woody species, Prunus serotina Ehrh., is an aggressive invader of forest understories in Europe. To better understand the plant invasion process, we assessed understorey plants and Prunus serotina seedlings that have colonized a 35- year-old replicated common-garden experiment of 14 tree species in south-western Poland. The density and size of established (> 1 year old) P. serotina seedlings varied among overstorey species and were related to variation in light availability and attributes of the understorey layer. In a multiple regression analysis, the density of established P. serotina seedlings was positively correlated with light availability and understorey species richness and negatively correlated with understorey species cover.

Citation

Knight, Kathleen S.; Oleksyn, Jacek; Jagodzinski, Andrzej M.; Reich, Peter B.; Kasprowicz, Marek. 2008. Overstorey tree species regulate colonization by native and exotic plants: a source of positive relationships between understorey diversity and invasibility. Diversity and Distributions. 14: 666-675.