Forest remnants in the Long Point region, Southern Ontario: Tree species diversity and size structure

Abstract

We investigated tree species composition, diversity and size structure of eight privately owned hardwood forest remnants and a 50 ha portion of semi-old-growth forest (Backus Woods) in the Long Point region, Southern Ontario. Our aim was to determine the degree to which fragmented forests in the region harbor and sustain tree species diversity and to provide a baseline for ongoing study of these forests. The eight woodlots collectively exhibited over 95% of regional tree species. Analysis of size structure within these woodlots suggested that many species were being replaced successfully. While Backus Woods was among the largest and most species-rich of the areas sampled, rates of species accumulation were often lower than in the woodlots, particularly in the understory. Selective cutting in the woodlots may explain this high understory diversity, which is marked by a greater importance of shade-intolerant tree species as compared to Backus Woods where minimum intervention management is practiced. We suggest that the privately owned, and largely unprotected, fragmented forests in this region be recognized for their high tree diversity and potential to sustain tree diversity into the future.