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Kandyd Szuba, Domtar Inc. on behalf of the VMAP team. Section VI: Landscape-level effects of Herbicide Reduction - Preliminary Results -. Background. A small area is treated chemically each year, but over time it adds up! ~ 12% of the Provincial Crown Forest in total, or
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Kandyd Szuba, Domtar Inc.on behalf of the VMAP team Section VI: Landscape-level effects of Herbicide Reduction - Preliminary Results -
Background A small area is treated chemically each year, but over time it adds up! ~ 12% of the Provincial Crown Forest in total, or ~ 24% of the AOU over 100 years.
Background cont. • Past focus on effects of herbicides on growth and yield and composition at the plot level and stand level • Potential for effects at landscape level over time
Objectives Use case studies to model potential effects of herbicide reduction in the context of: • The forest level (i.e., Sustainable Forest License [SFL]) • Approved forest management plans (FMPs) Assess: • What is the impact of reduced herbicide use on the ability to achieve the social, ecological, and economic objectives of an FMP? • Without herbicides, how much does it cost to achieve FMP objectives?
ApproachModels, Objectives, and Constraints I) Use SFMM models approved by MNR for the FMPs i) SF – non-spatial SFMM analysis ii) RMF – feed SFMM model into Patchworks for spatial analysis II) Add a brushsaw option for tending (with realistic cost) III) Modify growth & yield curves for brushsawing based on experimental trials* IV) Maintain existing FMP objectives and constraints i) SF ecological objectives = constraints in SFMM; wood supply = an outcome ii) RMF – Patchworks seeks a “good solution” that achieves all objectives; weights ecological objectives heavily * G&Y task team – Todd Little (Domtar – management forester), Mike Malek (MNR Resource Analyst), Ken Lennon (MNR Forest Productivity Specialist), with input from Wayne Bell (MNR research scientist)
ApproachYield Curve Modifications (NMV) SP1=upland black spruce; may contain up to 30% poplar
ApproachYield Curve Modifications (NMV) • No change to curves for brushsawing in: • jack pine (PJ1, PJ2), • lowland Ce-La-Sb mix (LC1), • boreal mixedwood (MW1, MW2), • poplar (PO1), birch (BW1)
ApproachEight Scenarios Run these scenarios: 1) Selected management alternative (SMA) from the approved FMP (normal budget (NB), full area available for herbicide application) 2) SMA & brushsawing (BR) & unlimited silviculture budget 3) SMA & BR & NB 4) SMA & BR & NB but only 75% of the SMA area available for herbicides 5) SMA & BR & NB with 50% area for herbicides 6) SMA & BRwith NB and 25% area for herbicides 7) SMA with NB and 0% of the area for herbicides 8) SMA with 0% of the area for herbicides and an unlimited silviculture budget Assess scenarios up to 60 years
ResultsHighlights – Stumpage to the Crown Direct revenue to the province. Excludes the stumpage charges paid for forest renewal & FRI.
ResultsHighlights – Road Distribution & Cost Sample Road network at 40 years – more dispersed with 100% herbicide reduction (right)
Results - HighlightsRoad Distribution & Cost Herbicide reduction requires a larger active road network. This results in higher maintenance cost and higher hauling cost per cubic metre harvested.
Results - Ecological Effects Some SFMM models would not solve because ecological targets were limiting LOTS of Old Growth!
Results - Ecological Effects Lots of habitat for the Black-backed Woodpecker! And other mature and old-forest loving species as less area was harvested
Results - Ecological Effects Less habitat for the American Kestrel
Results - Ecological Effects Less habitat for the White-throated Sparrow
Results - Ecological Effects Less moose browsing habitat
Preliminary Modeling Conclusions Some SFMM models would not solve for ecological reasons. Model choices were influenced by G&Y penalties (lower yield in some cases with brushsawing treatments), higher silviculture cost (up to ~2 times greater for brushsawing), and ecological constraints. • Herbicide reduction resulted in: • Less area harvested • Less SPF volume harvested (also with unlimited silviculture $$) • Lower net revenue to the Crown (also with unlimited silviculture $$) • A larger network of active roads • Higher cost for maintaining roads and hauling wood • More old growth (more than needed to meet ecological targets) • More habitat for wildlife preferring mature and old forest • Less habitat for species of young or recently disturbed forest (kestrel, moose, white-throated sparrow)