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An intersection of state and federal organizations, sharing and focusing science and management resources to elevate our understanding of natural resources. CENTRAL CASCADES ADAPTIVE MANAGEMENT PARTNERSHIP. YOUNG STAND THINNING AND DIVERSITY STUDY.
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An intersection of state and federal organizations, sharing and focusing science and management resources to elevate our understanding of natural resources. CENTRAL CASCADES ADAPTIVE MANAGEMENT PARTNERSHIP
YOUNG STAND THINNING AND DIVERSITY STUDY A management study evaluating the ecological, operational, social, and economic consequences of alternative methods of managing 30-50 year-old plantations.
TREATMENTS • Control (uncut, avg. 261 tpa) :Blue outline • Light thin (thinned to 105 tpa) :Yellow outline • Heavy thin (55 tpa) : Green outline • Light Thin with Gaps (same as light thin but with additional • 0.5 acre gaps over 20% of the treatment) : Red Outline
LIGHT THIN W/GAP TREATMENT Gaps planted • This treatment mimics mortality patterns of • small fires • root-rot outbreaks • Insects
HEAVY THIN TREATMENT • This treatment opens the canopy dramatically allowing • Rapid diameter growth • More understory development
LIGHT THIN TREATMENT • This treatment is similar to a standard commercial thin. • ~ 1/2 stems were removed • 110 trees per acre left
MONITORING • Small Mammals pre twice; post 2 & 3, 11 & 12 • Amphibians pre twice; post 11 + cover boards • Birds pre twice; post 3, 4, 5, 7, 11, 12 • Vegetation pre stand exams, post 1, 3, 5, 11 • Logging Costs post • Soil Impacts post • Snags/down wood post 2, 11 • Stand Damage post • Public Perceptions post • Arthropods post 5 and 6
Chanterelle’s MONITORING -- one year pre (1994), post 1996-7, 1999 KEY FINDING: • Chanterelle productivity significantly declined (but was not eliminated) immediately after thinning • the level of decline was greater in the heavily thinned stands than in those lightly thinned NO DATA COLLECTED TO SEE IF RECOVERED OVER TIME
Mushrooms www.pbase.com/ladislav/image/33934414 1996 1997 1999 2001 Short-term reductions Pilz et al. 2006
LOGGING DAMAGECompared tractor, cut-to-length, skyline, & helicopter KEY FINDINGS: • Most typical damage was scarring • Ground-based systems more severe • Skyline and helicopter: larger scars, gouging, and root damage • Damaged concentrated w/in 15 ft of skid trails / skyline corridor centerlines. • Cut-to-length systems -- harvester caused more wounding (70%) than forwarder (30%), but forwarder scars were larger and sustained severe gouging.
Litter Dwelling ArthropodsAffects of thinning complex! • Key Findings: • Seasonal affects override treatment affects • Indirect affects on litter moisture decreases abundance and diversity proportional to thinning • Control vs light thin – no difference • Light thin w/gaps – no difference from heavy
PUBLIC PERCEPTIONSPost-Thin, Heavy and Light KEY FINDINGS: • Both Treatments - low visual impacts met moderate scenic integrity standards
COMPACTION • KEY FINDINGS: CABLE • 0.5% of area was disturbed • Compaction negligible, but some sites -- decreased bulk density • From tilling of dragging tops??
COMPACTION – SLASH DEPTHS KEY FINDINGS: HARVESTER FORWARDER • 3-5 passes, compaction raised soil strength • no further increase in compaction • Existing OM, particularly rotten logs, cushioned and reduced compaction • Compaction was 21% at 4” depth, 12% at 8” • High levels of slash reduced compaction to a small extent • There was very little change in bulk density in the middle of skid trails at 8” depth
COMPACTION KEY FINDINGS: CUT TO LENGTH (harvester forwarder) • Difficult to reuse old skid trails due to difference in the systems used 50 years ago • New skid trail showed same compaction as old trails • Bulk density increased 12% • Over 20% oF area of compacted, still within FS guidelines