Fire history reconstructions show that historical fire regimes in montane forests of southeastern British Columbia were dominated by frequent lower-severity surface fires, that burned and scarred trees every 5 to 40 years for several centuries up to the 1900s.

Despite the historical frequency of fires and recent periods of suitable climate, these forests last burned causing fire scars 40 to 160 years ago – providing strong evidence of the effects of disrupted fire regimes during the 20th century.

The lack of recent fires is reflected in changes in tree composition and tree density. In absence of surface fires, dense understories of fire-intolerant trees persist, altering forest composition, structure and fuels.

Beginning in the 19th century, colonialist fire exclusion policies had a profound impact on First Nations’ homelands and cultural resources that persist today.

The exclusion of Indigenous cultural burning, followed by the cumulative effects of land-use change, early 19th century logging, even-aged silviculture, and fire suppression during the 20th century have altered the fire regimes and reduced the resilience of Canada’s montane forests.