Silviculture in Mazinaw-Lanark Forest

Quick Facts

• Mazinaw-Lanark Forest is the most southerly Crown forest management unit in Canada. This geographic location combined with the impact of geology, climate, land use history and ownership results in unusually high level of heterogeneity of the forest and very complex silviculture applied on the ground. Forest complexity is a major challenge but also a source of ecosystem resilience and beauty, which we strive to maintain.
• Out of over 30 tree species known to occur in the Mazinaw-Lanark Forest 17 are encountered in the day-to-day forest operations.
• Out of 25 forest ecosites known in Central Ontario 24 are represented in the Mazinaw-Lanark Forest.
• Average size of a forest stand in the Mazinaw-Lanark Forest is 6 hectares.
• Average area harvested each year on the Mazinaw-Lanark Forest represents less than 1% of the total productive forest area.
• Average proportion of silvicultural systems used on the harvested area:
  > SELECTION - 40%
  > SHELTERWOOD - 45% (of which ca. 15% is Commercial Thinning)
  > CLEAR CUT - 15%
• The silvicultural objective of all harvest is to maintain healthy, vigorous forest cover but not all harvest is designed to directly trigger regeneration process. For example such treatments as commercial thinning or preparatory cut under shelterwood system are implemented to achieve improvement in spacing, average quality and stand composition rather than removal of mature trees to be replaced by young cohort.
• 80-90% of harvested area in MLF regenerates naturally from seed and root sprouting, while 10-20% is regenerated through tree planting.
• The desire to maintain heterogeneous forest condition and the attempts to emulate natural disturbance combined with relatively low intensity of silviculture are not conducive to fully predictable and uniform management results. For example retention of various structural components for stability of habitat and continuity of natural heritage may occasionally impact the immediate needs of desired regeneration. Our overall results reflect constant balancing act between multitude of objectives and reality.