. The Canadian field-naturalist. 1991 Loope: Interrelationships of Fire, Land Use and Landscape 21 Based on sections from living fire-scarred trees, the average period since the last scarring fire in PRNL was 84 years (Table 1). In contrast, the average pre-settlement fire occurrence rate was one per years. A single section taken from a living Red Pine in the Beaver Lake area illustrates fire events from the early 18th century to the present, indicating a lengthening of fire interval in the 20th century (Figure 3). Fire scar evidence indicating a lack of fires since the 1910s is consisten
. The Canadian field-naturalist. 1991 Loope: Interrelationships of Fire, Land Use and Landscape 21 Based on sections from living fire-scarred trees, the average period since the last scarring fire in PRNL was 84 years (Table 1). In contrast, the average pre-settlement fire occurrence rate was one per years. A single section taken from a living Red Pine in the Beaver Lake area illustrates fire events from the early 18th century to the present, indicating a lengthening of fire interval in the 20th century (Figure 3). Fire scar evidence indicating a lack of fires since the 1910s is consistent with the increment core aging of large diameter individuals with unburned lower branches (Table 1). Vegetation transects in areas with evidence of fire show a prominence of White Birch and Red Maple along with pine species (Table 2). While both these hardwood species are mentioned in the GLO survey notes (Table 3), it can be inferred that they were not nearly as prevalent in 1850 as they are at present. Increment core ages of larger diameter White Birch (all less than 80 years) are consistent with post settlement establishment. No other clear changes in the gross character of the forest overstory are evident. The understory (Table 4) contains species typical of other fire prone forest stands of the region (Martin 1959; Curtis 1959), including blueberries, Vaccinium angustifolium and Vacci- nium myrtilloides, Trailing Arbutus, Epigaea repens, Wintergreen, Gaultheria procumbens, Cow Wheat, Melampyrum lineare, Wild Lily of the Valley, Maianthemum canadense, Braken Fern, Pteridium aquilinum and Star Flower, Trientalis borealis. Woody ground fuel loading measurements averaged (sd = ) tons/ac. (n = 17) while depth of needle litter accumulation and duff thickness averaged in. (sd = ) and in. (sd = ) respectively. Fuel data show high variability and no consistent geographic trends. In scattered patches (about 10% of the study area), young Black Spruce and B
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