Fencerow and forest edge vegetation structure in eastern Ontario farmland

The hypothesis that fencerow communities extend forest patches into the surrounding agricultural matrix as linear elements was tested by comparing species composition and vegetation structure of fencerows and forest edges in farmland of eastern Ontario, Canada. Species richness in tree, shrub and ground flora varied greatly among seven fencerows, but no difference in richness was found between the two edge types (fencerows and forest edges) in any stratum. Forest edge canopies were dominated by a single tree species, whereas fencerows had several co-dominant tree species. In lower strata, non-native species were a minor component of vegetation in both fencerows and forest edges; woodland species were well-represented in the forest edge flora, but not in fencerows. Grasses and fruit-bearing shrubs dominated subcanopy strata in fencerows. Forest edge species in all strata were mainly wind-dispersed and shade-tolerant. Fencerow species in all strata were mainly animal-dispersed and intolerant of shade. Analyses clearly distinguished the two edge types mainly on canopy tree species abundance. Fencerow vegetation structure provides no evidence for a developmental relationship between fencerows and forest edges in this landscape.