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Range Supply ReviewA Management Strategy for a Landscape
with Multiple Users
Tyler MorhartMinistry of Forests, Lands and Natural
Resource Operations
Dale GrossNature Conservancy
of Canada(Formerly FLNRO)
Overview• Background
• Multiple Use• Forage Supply Inventory
• Materials & Methods• Plant Communities• Final Product• Discussion• Summary
Background
• Peace District• Northeast British Columbia
• 226 Tenures/106,000+ AUMS• 621,766 Ha
• Long History of Multiple Use on Rangelands
Background–Multiple Use
Background–Forage Supply Inventory• Needed large scale inventory system to visualize:
• Forage type• Access• Developments• Carrying capacity
Materials & Methods• Identification of each plant community within every range tenure•Three transect of ten 0.5x0.5 m plots within each plant community• Vegetation removed from each plot and separated by structural class and palatability •Dried vegetation used to calculate kilogram per hectare palatable forage
Materials & Methods• Impossible to access every range tenure• Instead clippings collected from:
• Numerous sites and different plant communities• Stands of 0, 25, 50, 75 and 100% utilization
• Statistical range and average AUM productivity calculated for plant communities at different utilization levels
Plant Communities
• Peace Grassland•2‐3 ac/AUM
• Aspen low/tall forb• 6‐8 ac/AUM
Plant Communities
• Mixed woods• 15 ac/AUM
• Coniferous• 25‐30 ac/AUM
Plant Communities
• Peace Shrubland• 6‐25 ac/AUM
• Tame Grassland• 1 ac/AUM
Plant Communities
Harvested – No forage 1 year100% Access
Mature Aspen – 5‐6 acres/AUM100% Access3000 SPH
Year 2 (seeded) – 5 acres/AUM100% Access
Year 5 – 8 acres/AUM0‐10% Access35,000 SPH (range of regen 10,000 ‐80,000SPH)
Year 30 – 7 acres/AUM50% Access8000 SPH
• Aspen Regen
Final Product 1
Final Product 1–Polygons
Example: Polygon 2b represents a mixed wood site with white spruce trees ranging from 10‐15 m high. There is a lot of available forage within this area for the cattle and use is heavy 20 m into the bush from the tame and trails. Area is mostly flat with slight 5% W slope. Max carrying capacity is about 20 ac/AUM
Final Product 2–Multiple Users
Discussion• Strengths:
• Impacts of overlapping tenures are properly managed• Accurate estimates of acres per AUM on each tenure• Prevents over allocation• Ensures a healthy, sustainable ecosystem
•Weaknesses:• ‘Snapshot’ at the time of the inventory• Must reassess site conditions to ensure information remains current (trends)• Maps not yet digitized to public
Summary• Multiple users: large interest to public land use, from various users which have diverse impacts• Range supply review: plant community identification with averages for maximum potential carrying capacity and safe use (acres/AUM)• Long term goals: to meet the needs of multiple users while maintaining ecosystem integrity• Mapping helps identify and visualize cumulative impacts on land.
