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38 Cards in this Set
- Front
- Back
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silviculture system
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=silviculture treatment throughout the life of a stand including regeneration treatments, protection, or cuttings
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insolation
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-heat, temperature, and light quality
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who eats seeds?
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squirrels, mice, voles, shrews, and insects.
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Minimum light requirements for survival
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white spruce 12-15%
lodgepole pine 20% balsam fir 8% *growth rates differ by light levels |
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2 regeneration methods
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1. uneven aged
2. even aged |
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regeneration method
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=procedure by which a stand is replaced or renewed
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benefits of regeneration methods in uneven-aged stands
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used to maintain uneven-aged stands, maintain forest cover, provide a continuous flow of fiber
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What can be done to deal with temperature problems?
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1. select species adapted to local climate
2. break up organic soil layers to increase soil warming 3. leave residual trees for protection |
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maximum sucker production
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soil is 20'C in summer, and is inhibited when soil is below 15'C
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regeneration method components
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-removal of the old stand
-establishment of the new stand -treatment of vegetation, slash, or soil for favorable reproduction conditions |
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silviculture
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=the art and practice of growing forests
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vegetative reproduction
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1. sprouts
2. suckers 3. cutting 4. layering 5. coppice method |
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2 types of clearcut
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1. natural regeneration (seed, coppice)
2. artificial regeneration (aerial seedling, planting) |
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clearcutting
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stand is removed with regeneration occuring after harvest
2 types: natural regeneration artificial regeneration |
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reenter stands
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=have to maintain access
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natural shelterwood method
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stands that already have established regeneration in the understory
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3 steps in shelterwood method
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1. prepatory cuttings
2. establishment of seedling cuttings 3. removal cutting |
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even-aged
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(1 or 2 height or age classes of trees present)
-shelterwood -seed tree -clearcut |
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uneven aged
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(3+ height or age classes of trees present)
-selection |
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problems of regeneration methods in uneven-aged stands
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-expensive, need to frequently reenter stands, operate over large areas, yeild reduced, not well suited for intolerant species
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regeneration methods in uneven-aged stands
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-single tree selection of group selection
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lethal temp. for growth
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50'C is lethal
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why is clearcutting the method commonly used?
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-simplicity
-cost -yield -preferred for intolerant species -experience -equipment |
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environment
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factors include:
-insolation -moisture and drought -frost |
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coppice method
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-"Low-forest system"
=short forests over short period of time |
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what is used to improve light availability for seedling growth?
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-removal of overtopping vegetation
-vegetation management -cleaning -thinning |
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regeneration triangle
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1. seed supply
2. seedbed 3. environment *mandatory to have all 3 components |
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seed tree method
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(similiar to clearcut systems)
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seedling growth and survival
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-mortality can occur during first year of germination, usually in winter b/c of freezing, frost...
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sexual reproduction
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"High Forest System"
-by seed regeneration |
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seed supply
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= the amount and quality of seed that reaches seedbed conditions
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seed production variance
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=vairies with tree species, tree age, climate, and site conditions
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serotiny
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seed can remain viable inside of cones for several decades, and is released when cones are heated sufficiently high temp. by fire
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2 sources of regeneration
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1. vegetative reproduction
2. sexual reproduction |
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most favorable seedbed for germination
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-exposed mineral soil free of vegetation cover
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viability of seeds in the soil
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-lasts for 1 or 2 years
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dispersal of tree seed
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-influenced by many factors:
1. height seed is released 2. distance from seed source 3. characteristics of seed 4. wind |
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seedbed
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factors include:
-surface properties -depth of organic matter -vegetation cover -elevated microsites |
