The type and age of forests are important factors to consider when managing Saskatchewan's natural resources. Aging forests are more vulnerable to wildfire and disease. Forest management in Saskatchewan is designed to result in a forest age structure that emulates natural disturbance. By emulating natural disturbances, the natural range of ecosystems should be maintained, resulting in a more resilient system.
What we are doing
The province of Saskatchewan covers an area of approximately 65.2 million hectares The northern half of the province is largely covered by upland forests, wetlands and water. Grass and agricultural lands cover 36 per cent of the province, mainly in the south.
Four ecozones are found within the province: Taiga Shield, Boreal Shield, Boreal Plain and Prairie. The provincial forest covers approximately 34 million hectares within the Taiga Shield, Boreal Shield and Boreal Plain ecozones.
About 64 per cent of the provincial forest is an upland forest (41 per cent softwood, eight per cent mixedwood, seven per cent hardwood, and eight per cent open productive/shrub forest types). Wetlands and water each account for 17 per cent of the provincial forest. Grass, barren rock/sand, agricultural and anthropogenic areas make up the remaining 2 per cent of the landcover.
*For the purposes of this indicator, the 11.7 million hectare commercial forest zone has been expanded to include the Cold Lake Air Weapons Range, and provincial and national parks within and adjacent to the commercial forest zone. Within the provincial forest, the greatest amount of human activity occurs within this 14.3 million-hectare area referred to as the greater commercial forest zone.
The greater commercial forest zone is largely softwood, but features a greater proportion of hardwood and mixedwood forest types compared to the provincial forest. Wetlands also feature prominently within the greater commercial forest zone, covering nearly a third of the area.
Most forest-based economic activity and fire suppression occurs within the greater commercial forest zone. The greater commercial forest zone is subdivided into a number of timber supply areas. Presently, there are six active forest management plans, covering 8.3 million hectares.
Boreal forests, when uninfluenced by human activities, are shaped by natural disturbances like fire, insects, disease and wind. In theory, the greatest amount of forest area is typically found in the youngest forest ages, and the least amount of forest area is typically found in the oldest forest ages. In contrast, forests managed solely to sustain timber yield are evenly distributed among young, immature and mature forest ages with very little forest area in the old and very old forest ages. The greater commercial forest zone's current forest age structure falls between these two theoretical patterns.
Forest management in Saskatchewan is designed to result in a forest age structure that emulates natural disturbance, unlike a sustained timber yield approach. By emulating natural disturbances, the natural range of ecosystems should be maintained, resulting in a more resilient system.
Within the Boreal Shield ecozone, where fire suppression has been less intensive, forests typically follow a natural boreal forest pattern. This is evident for the portion of the greater commercial forest zone within the Churchill River Upland ecoregion.
Within the Boreal Plain ecozone, where protection from fire and insect damage has been a priority for over six decades, the proportion of mature and old forest ages are high relative to what is expected under natural boreal forest conditions. This is evident for the portion of the greater commercial forest zone within the Mid-Boreal Upland and Boreal Transition ecoregions, where the majority of Saskatchewan's forest harvesting has taken place. Here, from fire and insects has protection ensured a supply of mature and old age forest, and regulated harvesting has created a supply of young and immature forest. For the portion of the greater commercial forest zone within the Mid-Boreal Lowland ecoregion, where forest harvesting has been minimal, the forest is aging.
Why it matters
Forests must be managed in such a way as to balance habitat needs, recreational opportunities and economic growth. Like a well-diversified financial portfolio makes it easier to adapt to economic market changes, biological diversity makes it possible for ecosystems and species to respond and adapt to environmental change. Generally, forest management practices over the last number of decades in Saskatchewan have shifted the distribution of forest ages towards older classes in the greater commercial forest zone.
Where humans have been putting out wildfires for decades, the forest has become older than it would under natural boreal forest conditions. This can lead to more intense wildfires and more serious insect infestations. Letting wildfire play its natural role when safe and feasible is one way to address this age imbalance; carefully planned forest harvesting can be another.
Native plant and animal species are often associated with certain forest and wetland types and certain forest ages. The availability of habitat for various species may be partially assessed through the abundance and distribution of forest types, forest ages and wetlands. Maintaining the natural range of ecosystems results in a more resilient system, helping to sustain overall biological diversity. Ecosystem diversity, the variety and relative abundance of ecosystems and their plant and animal communities, is necessary for species preservation.
The ideal distribution of forest ages for any management area depends on the ecology and management goals for that area. In reality, the target forest age structure is somewhere in between the natural pattern and that of a forest managed solely for timber. What is important is that wood fiber, habitat and ecosystems are maintained.
Saskatchewan's forest management planning process emulates natural disturbances, allowing ecosystems to be maintained, resulting in a more resilient system. Resilient systems sustain biological diversity, protect habitat, maintain recreational opportunities and ensure economic growth.
More detailed information can be found in this technical report.