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4th year 2nd sem > BIOL 3447- Exam > Flashcards

BIOL 3447- Exam Flashcards

1
Q

what are the phases of silvicultural systems

A
  • regeneration -> tending -> harvesting
  • can be cyclical or as the interdependence of components
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2
Q

types of management

A
  • exploitation
  • non declining even flow: continued access to resources
  • balance structure: replenishment
  • wise use: use in the present and continuous supply in the future
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3
Q

exhaustible vs flow resources

A

exhaustible: resources of limited and finite amounts
flow: resources that are replenished to some degree

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4
Q

single cohort system

A
  • cohort establishment only at the beginning with replacement at rotation end
  • single age class managed as one unit- homogenous stand conditions
  • tending applied to promote development
  • some harvest of immature trees to promote growth and generate revenue
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5
Q

multi cohort system

A
  • wide range of age classes- typically 3 cohorts at different stages of development
  • tending and establishment of regeneration are concurrent
  • return to stand at intervals to control structure and maintain cohorts
  • periodic merchandising of logs to generate revenue
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6
Q

describe the different levels of intensity of management

A
  • wild: perfect alignment with ecological development, small amount of timber management if possible, may include protected areas or areas too remote for timber
  • regulated: moderate alignment with ecological development, managed through ecological forestry, balance biological and commodity goals
  • domesticated- managed through technological forestry, best conditions for growth, high levels of investment
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7
Q

describe the factors affecting silvicultural decisions (5)

A
  • accessibility (constructing roads)
  • markets (is there a market to support the cost of growing timber)
  • site quality (is the site of good enough quality to support growth)
  • tree character and conditions (are the trees of good quality)
  • ownership
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8
Q

economic costs of silviculture

A
  • access- can you get to and process the wood at a reasonable cost?
  • interest- does anyone want the product and what price are they willing to pay?
  • timing- how quickly can you get the product to market
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9
Q

economic values of silviculture

A
  • wood as a resource- easy to harvest, good insulating properties, strong and durable, can be harvested relatively endlessly
  • stumpage- price on standing timber and the right to harvest it
  • user fees- recreational opportunities, access to easement and conservation areas
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10
Q

types of timber harvesting systems

A
  • whole tree: removal of the entire tree (stem, branches, stump, roots) to the landing
  • tree length: felling, topping, and delimbing trees in the forest, tree is bucked at the landing or mill
  • cut-to-length: felling, topping, and delimbing the tree in the forest, tree is bucked in the forest
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11
Q

describe some of the effects of silviculture on the ecosystem

A
  • skid trails: temporary roads/trails used by logging equipment to remove logs
  • machinery equipment may leave ruts or disturb soil
  • increase in overland flow and mobility of debris and foreign chemicals
  • removal of vegetation decreases shade and increases water temp
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12
Q

best management practice

A
  • optimal operating methods for preventing or reducing water pollution and protecting wetlands
  • includes planning of transportation, appropriate retirement, planting landings, limiting how many roads can be in use at one time
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13
Q

US clean water act (crown sustainability act)

A
  • BMPs can be applied to landings, skid trails, truck roads, stream and wetland crossings, harvests by water
  • includes installing water barres and culverts, leaving buffer strips, planning, seeding with stabilizing plants, controlling the season, controlling slash, periodic maintenance, retirement
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14
Q

airborne laser scanning data

A
  • digital surface model: elevation model that captures the environment’s natural and artificial features
  • digital elevation model: representation of the bare ground (exclude surface objects)
  • canopy height model: maps tree height as a continuous surface, DSM-DEM
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15
Q

how can LiDAR be used to facilitate planning

A
  • allows you to plan where best to do things:
    • shut down skidding in saturated areas
    • place landings on soft gradients
    • prohibit machinery from stream side buffers
    • make sure roads and trails are kept in good condition
  • predict costs based on current surfaces
  • detect ephemeral streams (important habitat features)
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16
Q

how can water systems be protected

A
  • riparian zone (interface between land and water) protection (maintain litter, reduce sedimentation, maintain shade)
  • buffer strip: strips of vegetation that provide a physical barrier to slow the flow of water and reduce runoff
  • filter strip: a narrow strip of vegetation that acts as a barrier to pollutants into the waterways
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17
Q

describe the timeline of planning and implementing a harvest

A
  • schedule operations to avoid critical times
  • use machine operation strategies that minimize litter disturbance
  • design trails/roads to keep the surface dry
  • maintain landings to prevent erosion
  • match equipment and practices to the needs and conditions
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18
Q

fire triangle

A
  • oxygen: fire is an oxidation reaction
  • fuel: any combustible material, affected by moisture content and piece size
  • heat: fire occurs when fuels are heated up beyond their ignition temperature, water is an effective fire suppressant because of its high heat capacity
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19
Q

describe the different types of fires

A
  • ground fire: burn below the surface, low frequency-high impact, long recovery, alters soil chemistry dramatically
  • surface fire: burns lightweight fuels at the surface, moderate temperatures, high frequency- low impact, short recovery
  • crown fire: high fuel loads with ladder fuels, low frequency- high impact, long recovery, resets the system for succession
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20
Q

ignition

A
  • requires activation energy to initiate the reaction
  • most common forms of ignitions are lightning and humans
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21
Q

what affects the spread of a fire (5)

A

fuel loads, landscape connectivity, topography, hydrology, wind

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22
Q

general fire hypothesis

A

communities of plants have evolved with a fire regime and thus depend on fire

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23
Q

what do forests require for fire to play a significant role (4)

A
  • ignition sources
  • appropriate fuel structures (type of fuel determines the type of fire)
  • seasonality (at least one season with warm dry conditions)
  • sufficient productivity
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24
Q

describe the best fuels

A
  • high SA:V (fine twigs)
  • low moisture content
  • high concentration of flammable compounds (terpenes)
  • varied (encourages consistent fire)
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25
Q

fire adaptations (5)

A
  • thick bark
  • high foliage/self pruning
  • sprouting (persistence adaptation)
  • stimulate germination
  • serotiny
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26
Q

describe the longleaf pine system

A
  • seedlings germinate on mineral soil and have rapid growth
  • grass stage- secondary needles and buds have protective resins, juvenile bank to survive fire
  • mature trees have thick corky bark
  • fire controls pests and competition
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27
Q

describe the clearcutting system

A
  • even age forest of shade intolerant species
  • emulates large disturbances
  • emphasis on light penetration to support regeneration
  • applied as a mosaic over the landscape
  • cost efficient and simple
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28
Q

what does a successful clearcut require

A
  • sufficient seed source
  • receptive seed bed
  • timely management of competition
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29
Q

types of clearcuts

A
  • conventional (complete removal of overstory)
  • clearcut with standards (veteran trees are retained)
  • seed tree (trees of seed bearing age are retained and dispersed throughout the stand, maintains structural diversity)
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30
Q

clearcuts in Ontario

A
  • retention of 10-36% of original stand
  • minimum of 25 snags per ha
  • variable sizes
  • new clearcuts separated from older clearcuts
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31
Q

modified clearcuts

A
  • patch clearcut: patches are harvested in various shapes and sizes reflecting the underlying forest mosaic
  • strip clearcut: adjacent strips cut sequentially, strip size and orientation regulated by ecological conditions, eventual coverage of entire stand
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32
Q

describe the importance of seed sources

A
  • harvest removes seed trees
  • few species have a viable seed bank
  • maximum widths are determined by the distance to adjacent seed sources
  • site variation and advanced regeneration will influence regeneration sucesss
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33
Q

environmental effects of clearcuts

A
  • increases surface and soil temps
  • increases evaporation and decreases humidity
  • increases soil moisture (reduced interception of precipitation, increased infiltration and percolation)
  • greater overland flow
  • faster decomposition
  • nutrient release
  • leaching
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34
Q

what microsite factors influence clearcuts

A
  • slope- the steeper the slope the better draining the soil and more susceptible the site is to drought
  • aspect- southern aspect is associated with a decline in regeneration
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35
Q

describe the different types of retention

A
  • provides habitat refuge, travel corridors, legacies, visual appeals
  • dispersed: retained trees are spread throughout the area
  • aggregate: retained trees are concentrated into habitat island- possibly more attractive to different species, provides operational value
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36
Q

slash

A

provides temperature moderation, protection fro herbivores, more suitable microenvironment, slow release of nutrients

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37
Q

describe the changing face of clearcuts

A
  • historically, clearcuts had straight edges, square corners, and retained trees were isolated to thin strips along streams
  • total, patches or bands of trees are retained throughout the site, there may be a mixture of aggregate and dispersed retention, greater visual appeal, diffuse boundaries
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38
Q

free to grow status

A

stands that meet stocking, height, and/or height growth rate as specified in the ground rules and are judged to be healthy and essential free from competing vegetation

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39
Q

silvicultural success

A
  • all standards contained in the silviculture ground rule applied to that stand have been met
  • e.g. standards for target species, acceptable species, future forest condition, wildlife habitat
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40
Q

clearcut advantages

A
  • high yields and low costs
  • regeneration of shade intolerant species
  • easy site prep and machine access
  • pest control
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41
Q

clearcut disadvantages

A
  • dependence on seed rain/bank and risk of failed regeneration
  • intense competition
  • reduced transpiration effects and high evaporative demand
  • soil disturbance and erosion
  • increased fire risk
  • loss of habitat
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42
Q

shelterwood characteristics

A
  • single cohort of mid-tolerant species
  • emulates moderate disturbances
  • primarily used with natural regeneration- new cohort develops under older trees
  • sufficient canopy cover to mitigate change in microenvironment
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43
Q

phases of a shelterwood

A
  • remove: removing trees to modify the light environment and benefit regeneration
  • retain: retaining adequate cover to create seed and a positive environment for seedlings
  • maintain: producing the regeneration niche of the species you’re trying to regenerate
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44
Q

cuts in a shelterwood

A
  • prep cut: removing inferior trees, allow more room for good trees, gives time for seed to be produced
  • seed cut: opening the canopy to 50%, hope that trees drop seed, allow for regeneration
  • removal cut: most of the shelterwood is taken off, a few residual stems are left
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45
Q

seed tree method

A
  • appropriate number of individual trees are left across an open area to provide seed for production of the next crop of trees
  • used for species that do well in open conditions but are limited by seed dispersal
46
Q

seed tree

A

residual stem that is a source of seed for the regenerating cohort

47
Q

characteristics of good seed trees

A
  • upper canopy position (access to resources)
  • thick stem relative to height
  • well balanced symmetrical crown
  • wind firm morphology
    • large, medium dense crowns, tallness, and poor root anchorage makes trees more susceptible to wind
48
Q

forest regeneration success

A
  • height and durability of seed trees
  • frequency of seed crops
  • seed production (related to crown size and stem thickness)
  • seedbed suitability
  • seed viability and germination rates
49
Q

shelterwood with reserves method

A
  • individuals are selected and left to overtop the new cohort
  • typically large diameter trees are retained at a low density
  • rarely used in NA forestry
50
Q

advantages and disadvantages of shelterwood with reserves method

A
  • D: increased variability in light environment, slower growth rate, trees may become flat topped
  • A: more growth on retained, more aesthetic, maintains certain habitat features
51
Q

characteristics of reserve trees

A
  • longevity (50-80 yrs)
  • good form, no lean, dominant/codominant crown
  • no dead/dying branches or epicormic branching
  • species not prone to dieback
52
Q

strip shelterwood method

A
  • parallel strips of 1 tree length in width are cut in successive entries
  • creates progressive canopy openings until a majority of the stand has mature age class removed
  • even aged stand
  • initiates regeneration and ensures everywhere is close to viable seed
53
Q

group shelterwood method

A
  • creates patches of regeneration dispersed throughout the site
    patches are circular and approx 1 tree length in diameter
  • cuttings expand patches until they coalesce
54
Q

benefits of shelterwood

A
  • vertical structure
  • variation in environment/density
  • legacy trees
  • transition habitat
55
Q

objectives of selection silviculture

A
  • sustained and regular yields
  • stable structure and forest conditions
  • full site utilization- optimal stocking and production of quality timber
  • regular replacement of mature trees
  • habitat availability
56
Q

characteristics of selection

A
  • multiple cohorts
  • high live crown ratios
  • high vertical structure (foliage at all layers)
  • wide range of diameters
  • strong height:diamter relationship (based on vigour)
57
Q

working cycle

A

forest under a particular work plan- the area where one silvicultural system is specified

58
Q

balance

A
  • each age/size class occupies the same amount of crown space (many small, few large)
  • regulating densities in each cohort maximizes site occupancy
  • negative correlation between crown size and density (lower density leads to larger crowns)
59
Q

q factor

A
  • describes the slope of the exponential curve relative density to diameter classes
  • q= # of trees in class (n)/ n+1
60
Q

problems with q type structure

A
  • idealized ratio and not a realistic representation
  • underestimation of ingrowth in spacing and pole size classes
  • divergence of economic and biological effects
61
Q

steps in the selection system

A
  • inventory of stand composition and structure
  • identify the diameter classes for cohorts
  • determine the appropriate residual density and cutting cycle
  • compare actual diameter distribution to desired structure
  • write a marking prescription to remove excess trees from overstocked size classes
  • mark and cut the stand
62
Q

retention priorities

A
  • target age class
  • vigour, form, soundless, low risk
  • species
  • crow position
63
Q

rehabilitating a degraded stand

A
  • retain an appropriate residual density even if high risk or low vigour trees are retained
  • plan for 2-3 cuts to upgrade the stand over time
  • choose a lower residual density and extend the cutting cycle
  • lower the max diameter and retain some suboptimal trees
64
Q

regeneration in the selection system

A
  • reduce the stocking of each diameter class
  • removal of mature age class to release developing stand
  • aim to propagate and promote the highest quality individuals int ehe and and allow them to replace inferior individuals
65
Q

effects of selection post harvest

A
  • high residual stand density
  • small increase in soil moisture and nutrients
  • increase in diffuse light in the understory
  • short term increase in temp and decomp
66
Q

variation in the light environment after selection harvesting

A
  • increases depth of light penetration
  • ground remains in partial shade
  • saplings under gaps are stimulated
  • germination and establishment of shade tolerant species is promoted
67
Q

foliage height diversity

A
  • proportion of total foliage at different height s
  • low score is associated with foliage concentrated in a few layers
68
Q

establishment

A
  • important for revegetation a stand
  • requires germination, shoot system penetration, and root system penetration
  • requires net positive assimilation as soon as possible
69
Q

site preparation

A
  • deals with changes of conditions that favour the species you’re trying to manage
  • can be done before or after
  • alters the physical environment or deals with competing vegetation
70
Q

goals of site prep

A
  • vegetation control
  • litter removal/mixing
  • promotes decomposition
  • alters nutrient balance
  • modifies habitat and enhances conditions
  • reduces fuel
  • facilities operations
71
Q

passive site prep

A
  • side effect of another activity- unpredictable
  • often couple with natural regen
  • skid trail mix soil, damage competing vegetation, and create a mineral seed bed
72
Q

active site prep

A
  • intervention to enhance the regeneration process
  • varied in intensity and extend depending on the application
  • controlled and more expensive
73
Q

what are the types of site prep

A
  • mechanical: altering the soil or litter, reducing competing vegetation, usually with machines
  • chemical: application of fertilizer or herbicide
  • fire: kill or reduce competition and reduce organic debris
74
Q

extent of site prep

A
  • broadcast: affects the entire stand
  • strip: applied in narrow alternating bands
  • spot: focused exclusively on the development of seedlings
75
Q

types of mechanical site prep

A
  • blading: bulldozers with blades that skim the surface
  • bedding: elevating cultivated bed to promote drainage and aeration
  • chopping/shearing: heavy rollers crush and separate debris (woody mulch)
  • chaining: chain is dragged behind a bulldozer, promotes decomposition and aeration
76
Q

advantages and disadvantages of mechanical site prep

A
  • A: slash management, mulching, vegetation management, improving drainage, scarification
  • D: erosion, compaction, weeds, sprouting, nutrient loss, temperature variation
77
Q

chemical site prep applications

A
  • individual stem
  • broadcast: larger areas
    • aerial: can treat hundreds of ha, only requires a few personnel, tightly restricted, must be applied at the correct time
    • ground level: only practical with good access and practical quantity, more targeted, require more volume and people
78
Q

advantages and disadvantages of chemical site prep

A
  • A: wide spread efficacy, sprout prevention, lack of forest floor disturbance, cost effective
  • D: off target damage, variation in efficacy, timing requirements, increased fuel loads, restrictions
79
Q

prescribed burning

A
  • controlled use of fire under conditions that permit its containment to a pre-determined area
  • produces a specified intensity of heat and rate of spread to satisfy the planned objectives and provide the desired benefits with minimum damage at an acceptable cost
  • a practical tool used in parks
  • associated with the management of mid-tolerant species
80
Q

fire weather index

A
  • based on temperature, relative humidity, wind speed, and rain
  • varies from 0-23 (cooler, wetter conditions have lower scores)
81
Q

types of prescribed fire

A
  • strip: light a protective back fire that consumes any fuel to prevent fire from burning past that point, then light a strip that slowly burns towards the back fire
  • spot: similar to strip but uses patches
  • ring: back fire is lit, perimeter of the burn area is lit and produces an updraft that causes rapid and intensive spread into the centre
82
Q

advantages and disadvantages of prescribed burn

A
  • A: slash and debris removal, nutrient release, vegetation and pest control, fuel reduction
  • D: release of toxins, narrow range of conditions, risk of escape, temporary, erosion, nutrient leeching
83
Q

12 points from the big meadow fire

A
  • prescribed fires reduce hazardous fuel to restore forest structure and composition
  • get fires back into the ecosystem
  • reduces severity of future fires
  • window of very specific conditions
  • maintain fire resistant vegetation
  • previous fire suppression
  • fire knowledge has evolved
  • limitation to when burns can occur, so burn whenever you can
  • burn area is heterogenous
  • regrowth involves different phases
  • emergency response team investigates after
84
Q

choosing a site prep treatment

A
  • vegetation present/desired
  • distribution of species/debris
  • topography and substrate
  • planned management
  • anticipated costs and benefits
85
Q

plantation

A

a forest community or stand established artificially by sowing or planting

86
Q

reasons for tree planting

A
  • lack of seed source
  • establish tree cover in an altered enviro (e.g. abandoned agriculture field)
  • control composition, spacing, arrangement
  • narrow window of conditions for establishment
  • problematic natural regen
87
Q

objectives of tree planting

A
  • products
  • protective cover
  • visual appeal
  • animal food and cover
  • windbreaks
  • ecosystem restoration/rehabilitation
88
Q

urban forestry

A
  • urban grove: a small closed tree community in undeveloped part of a city, unplanted
  • urban savannahs: strips of street side trees widely dispersed or in isolated clusters of small trees in open groves or parks, planted
  • paving trees: widely dispersed individual trees
89
Q

role of plantations in conservation

A
  • mimics natural disturbance
  • focus on native species
  • conserves woody debris
  • longer rotation
  • early thinning
90
Q

selecting the right species for artificial regen

A
  • must consider the goal of the plantation
  • cover, landuse history, climate, aspect, soil
91
Q

translocation rules

A
  • seed cannot be moved more than 161 km in distance or 150-300 m in elevation
  • donor and recipient site should be similar
92
Q

biological potential

A

rate of germination

93
Q

cold stratification

A

the process of exposing seeds to cold and moist conditions to encourage germination

94
Q

scarification

A

the process of altering the seed coat to allow for quicker water absorption and improve germination rate

95
Q

sowing rate

A

the density of seed to spread in order to achieve a given stocking level (seeds/unit area)

96
Q

seed certification

A

verification of the source of the seed and an assessment of the relevant properties of the seed lot

97
Q

seed lot

A
  • cohort of seed gathered from the same source during the same year
  • seed may differ from year to year, so seed lot tell you about viability and germination rates
98
Q

types of seed

A
  • unclassified seed: no info on where it comes from or its quality
  • source-identified seed: from good natural stands or plantations where the location is registered, no additional attributes but tells you if its from the right seed zone
  • selected: seed from a specific genotypes
  • certified orchard seed: the highest level, proven by progeny test, highest quality with specific attributes from the best genetic line
99
Q

bareroot seedlings

A
  • grown without pots or containers and shipped free of any medium around the roots
  • must consider: temperature, soil moisture, and seedling activity
  • spring is the best time to plant
100
Q

limitations of bareroot seedlings

A
  • seedlings must be lifted at an appropriate time for planting
  • seedlings deteriorate quickly after lifting and most be stored properly or planted immediately
  • seedlings must be handled with care
  • difficult to plant
101
Q

container stock

A
  • grown in a receptacle filled with soil or other rooting medium and out planted with the rooting medium left undisturbed around the roots
  • various containers and rooting media are used to maximize performance
102
Q

advantages of container stock

A
  • control of growing conditions
  • shorter nursery rotations and faster early growth
  • uniform size and condition
  • higher survivor ship
  • much easier to plant
103
Q

limitations of container stock

A
  • high production cost
  • technical difficulties with production
  • heavier than barefoot
  • vulnerable to frost heave
104
Q

intermediate treatments

A
  • deliberate cutting used to thin out a stand to provide more resources to the retained trees
  • improves spacing, composition, and vigour
  • includes release treatments (sapling) and thinning (post sapling- pre commercial/commercial)
105
Q

low thinning

A
  • RC- lowest crown positions and overtopped trees
  • R- upper canopy dominants, focusses growth on larger trees
  • E- decreases vertical density, improves quality
106
Q

crown thinning

A
  • RC- dominant and codominant crown positions, poor vigour and quality
  • R- upper canopy dominants, favours best growing stock, fillers and trainers
  • E- inform spacing, improves diameter growth, maintains some vertical diversity
107
Q

selection thinning

A
  • RC- diameter limit, low quality/value species
  • R- smaller trees, good growth form, promotes a certain species
  • E- best genetic stock is removed, poor natural regeneration, decreased yield
108
Q

free thinning

A
  • RC- spacing out crop trees
  • R- uniform spacing or strips in natural stands, rows in plantations
  • E- higher volumes from thinning, little changes in vertical structure, variety of trees retained
109
Q

how is a thinning method chosen

A
  • present stand conditions
  • species mixture
  • stand age (time to rotation, self thinning)
  • landowner objectives (product
  • end use (market, non-timber values)
110
Q
A

4th year 2nd sem (6 decks)

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