Premium
Why forests appear resistant to exotic plant invasions: intentional introductions, stand dynamics, and the role of shade tolerance
Author(s) -
Martin Patrick H,
Canham Charles D,
Marks Peter L
Publication year - 2009
Publication title -
frontiers in ecology and the environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.918
H-Index - 164
eISSN - 1540-9309
pISSN - 1540-9295
DOI - 10.1890/070096
Subject(s) - ecology , invasive species , ecological succession , introduced species , biology , disturbance (geology) , temperate rainforest , temperate forest , temperate climate , native plant , understory , ecosystem , paleontology , canopy
Invasion ecology has traditionally focused on exotic plant species with early successional life‐history traits, adapted to colonize areas following disturbance. However, the ecological importance of these traits may be overstated, in part because most invasive plants originate from intentional introductions. Furthermore, this focus neglects the types of plants most likely to invade established communities, particularly forests – namely shade‐tolerant, late‐successional species. In invasion ecology, it is generally assumed that undisturbed forests are highly resistant to plant invasions. Our review reveals that this assumption is not justified: in temperate and tropical regions around the world, at least 139 exotic plant species are known to have invaded deeply shaded forest understories that have not undergone substantial disturbance. These exotics present a particular management challenge, as they often increase in abundance during succession. While forest invasions may develop comparatively slowly under natural disturbance regimes, anthropogenic processes, including the spread of exotic pests and pathogens, can be expected to accelerate the rate of invasion.