Background/Question/Methods - The combination of forest inventory and satellite-derived landscape composition and structure provides otherwise unavailable information on regional forest conditions and enables investigation of the cumulative effects of forest management over time. Forest pattern results from disturbance events, such as fire or harvesting, or as a function of landscape position, soils, and climate.  We used new, national datasets of Canadian forest composition and fragmentation to describe forest pattern throughout Vancouver Island, British Columbia (>32,000 km²), relating it to inventory-derived forest age structure at the watershed level (n=1283 forested watersheds).  Vancouver Island is extensively forested, possesses high value and productive forests, and is managed to meet a range of stakeholder interests.  Fragmentation metrics were derived from a 25-m land cover map (i.e., grain) on a 1 km grid (i.e., extent), as developed for the entire forested area of Canada.  We summarized fragmentation island-wide and compared trends between forest dominated (> 85 % forest cover) and less forested (< 85 % forest cover) watersheds.  We also explored these patterns with partial canonical correspondence analyses to determine the independent and shared relationships of landscape composition, fragmentation and space with forest age structure. 

Results/Conclusions - As expected, less forested watersheds are more fragmented than forest dominated watersheds, exhibited as higher numbers (5.6 vs. 2.7) of smaller (36 ha vs. 63 ha) forest patches with a higher edge density (82 vs. 55 m/ha).  Island-wide numbers are similar to those of forest dominated watersheds.  Forest age is strongly related to landscape composition and fragmentation, which collectively explain 27% and 53% of the age structure of all and less-forested watersheds, respectively.  In both watershed sets, young stands are associated with broadleaved forests, agreeing with successional expectations, and patchy forest distributions.  Over all watersheds, old growth stands are associated with dense coniferous forest, but also with early successional communities, small patch sizes, and high edge densities, indicating fragmentation of these forests (related to mandated protection of stands of older forests within harvested areas).  In contrast, watersheds with an abundance of mature forest are compositionally similar to those with old growth, but are much less fragmented.  Fine-resolution, large-extent earth observation products, as are now available for the entire forested area of Canada, provide valuable insight into spatial and temporal forest dynamics (succession, harvesting).  On Vancouver Island, forest age reflects landscape composition and, although they are being conserved, large old growth stands are not maintained within a continuous forest matrix.