The Study of Silvics __________________

Readings for today’s lecture Klinka et al Pages Burns and Honkala. Pages 1-11.

What is silvics and why is it important? Silvics: Silviculture: Forest management: Ecosystem classification:

Tree species Conifers (18) Western hemlock Mountain hemlock Western redcedar Alaska yellow cedar Amabilis fir Grand fir Subalpine fir Douglas-fir (coast, interior) Sitka spruce Engelmann spruce White spruce (interior spruce) Black spruce Western white pine Whitebark pine Lodgepole pine Jack pine Juniper Western yew Deciduous (10) Red alder Bigleaf maple Black cottonwood Pacific madrone Garry oak Trembling aspen Paper birch Balsam poplar Mountain alder Sitka alder

Main Silvics Topics General description (nomenclature, distribution, identification characteristics, botanical features) Ecological characteristics (habitats, tree species associates, tolerances to environment) Life history (seed production, germination, form and size of mature trees) Genetic variation Silvicultural applications

Ecological characteristics Geographic range (distribution in North America) Climatic amplitude (climate class, BEC zones) Orographic amplitude Edaphics (SMR, SNR) Shade tolerance Frost and flood resistance Resistance and risk to damaging agents Silvical characteristics Tree species associates

Geographic range AreaRegion 1. Western North America Pacific Cordilleran Central 2. Eastern North America 3. Northern American transcontinental 4. Asian and North American 5. Circumpolar

Frequency of occurrence (infrequent): frequent: very frequent:

Climatic amplitude Indicates species climatic tolerances Characterized by climatic regions and climatic characteristics of BEC zones

Climatic regions used to describe climatic amplitude Climatic regionCharacteristics Arctic tundra =High Arctic MTWM<10 o C; MMT<0 o C 9-11 mo. Alpine tundraMTWM<10 o C; MMT<0 o C 7-9 mo. SubarcticCold, snowy climate with MTWM>10 o C; 2 mo. with MMT>0 o C. Montane borealCold, snowy climate with MTWM>10 o C; MTCM 10 o C. Subalpine borealSimilar to montane boreal but higher snowfall, shorter growing season, and cooler daytime temp. TemperateCold, snowy boreal climate but > 4 mo. with MMT>10 o C. Semi-aridEvaporation>precipitation; no headwaters MesothermalMild, rainy climate with MTCM -3 o C TropicalMTCM>18 o C

Continentality strata StratumCharacteristics Hypermaritime Martime Submaritime Subcontinental Continental

Example: Climatic amplitude of Amabilis fir Maritime subalpine boreal –(wet cool temperate) – wet cool-cold mesothermal Description includes (1) continentality stratum, (2) temperature or precipitation variations where they exist, (3) climate class Ordered left to right from coldest to warmest

Orographic amplitude ( general relief in conjunction with climate) Orographic class Species distribution Submontane Montane Subalpine Alpine

Species occurrences in biogeoclimatic zones Biogeoclimatic ZoneAbbrev.Climate Alpine TundraATAlpine tundra Mountain HemlockMHMaritime subalpine boreal Coastal Western HemlockCWHWet cool (cold) mesothermal Coastal Douglas-firCDFDry cool mesothermal Engelmann spruce-subalpine firESSFCool continental subalpine boreal Spruce-Willow-BirchSWBCold continental subalpine boreal Montane SpruceMSMild continental subalpine boreal Boreal White and Black SpruceBWBSCold continental montane boreal Sub-boreal SpruceSBSMild continental montane boreal Sub-boreal Pine - SpruceSBPSCool continental montane boreal BunchgrassBGCool semiarid Ponderosa PinePPDry cool temperate Interior Douglas-firIDFMoist cool temperate Interior Cedar-HemlockICHWet cool temperate

Edaphic amplitude Soil Moisture Regime 1.XD (extremely dry) 2.ED (excessively dry) 3.VD (very dry) 4.MD (moderately dry) 5.SD (slightly dry) 6.F (fresh) 7.M (moist) 8.VM (very moist) 9.W (wet) 10.VW (very wet) (infrequent), light green on edatopic grid frequent, green very frequent, dark green Amabilis fir:SMR (slightly dry) – fresh – moist – very moist – (wet) SNR: very poor – poor – medium – rich – very rich Soil Nutrient Regime 1.VP (very poor) 2.P (poor) 3.M (medium) 4.R (rich) 5.VR (very rich) Soil mineralizable N Water deficit AET/PET<1.0 No water deficit Demand=supply Water table present in growing season

Successional role and tree species associates Occurrence in naturally established stands Successional role Occurrence in pure and mixed species stands Area and extent of association with other tree species

Shade tolerance and exposure classes ClassDescription Shade tolerant Moderately shade tolerant Shade intolerant Protection requiring Exposure tolerant Exposure requiring

Species tolerances TolerancesCriteria Frost Heat Drought Flooding Nutrient deficiency or excess

Damaging Agents Damaging agentCriteria Snow resistance or resilience Wind resistance Fire resistance and risk Insect and pathogen risk

Silvical characteristics CharacteristicConsiderations Reproduction capacity Seed dissemination capacity Potential for natural regeneration in low light and in the open Potential for initial growth rate (<5 years) Response of advance regeneration to release

Silvical characteristics CharacteristicConsiderations Self-pruning capacity in dense stands Crown spatial requirements Light conditions beneath mature closed canopy Potential productivity Longevity