Final review Flashcards
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| What is the definition of forest inventory</p>
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process and procedure for obtaining information on the quality and quantity of the forest resources and many of the characteristics of the land area on which the trees are growing. Complete forest inventory for timber evaluation provides the following: estimates of area; description of topography, accessibility, operability; estimates of timber quantity and quality; estimates of growth; estimates of depletion.</p>
Classes of timber inventories:
Recce cruises: exploratory, extensive forest inventory with no detailed estimates obtained. No formal sampling design used
Timber Supply: detailed, extensive inventory of an area managed as one unit. (tree farm licenses, wood lots have periodic inventories)
Operational Cruise: intensive forest inventory of a small area that is planned for harvesting
100% sample: menas that every tree in the area is measured. seldom used because of time and expense involved.
Define and provide an example of sampling with regression estimators
used to increase the precision and efficiency of a sample by making use of supplementary info about the population being measured. supplementary info is data that is gathered at the same time as the regular data at a minimum cost.
EG:In cruising using variable plots we gather data on a basal area at no extra cost while measuring volume.
Define and provide an example of double sampling
similar to sampling useing regression estimators, except that population value for the supplementary variable is unknown. Population value for the supplementary variable is estimated from a large sample. EG) in cruising the supplementary variable we use is basal area/ha
combining the two variables gives us a better overall estimate of the timber volume on the area at a reasonable cost
Define 3p sampling
Probability Proportional to Prediction.
not widely used.
Kind of a combo of 100% sampling, and regression estimators, and simple random sampling.
EG) each tree in the cruise area is estimated and recorded, teh est value is compared to a random number, if est value is greater than the random number, the tree is sampled. this gives the volume/estimate ratio
Ministry Check Cruise Tolerances:
DBH Line: +/- 6.5 cm from true breast height
DBH MEASUREMENT: must be within 2% of actual (25 cm DBH +/- 0.5cm)
MISSED TREES: max 1 tree in 50 sampled
HT MSMNTS: max 5% variation (30m tree +/- 1.5 m)
PATH CALLS: Max 10% of all trees checked in a cutting authority can have a risk group change
6 Pieces of info required on a cruise plan map
Turning Point Forest Region POC cruise Timber Type Boundary Walk through plot BEC zone
what does PSYU stand for
Public sustained yield unit
FIZ
forest inventory zone( up to 13 zones in bc)
2 ways final cruise map differs from cruise plan map
actual plot locations on final map
volume info on final map(actual derived volumes)
why do licensees default to 100 m grid when cruising
Because if you go >100m, then you automatically have to meet specific # for sample error. If you do 100m grid, 1 plot/ha, MOF waives sample error
What is the purpose of a cruise compilation?
Its a combo of operational cruise data collected and standard formulas used to derive volumes, etc. Only deals with operational cruising side of equation(stand factors)
it’s around 50% of appraisal number
appraisal numbers generate stumpage
define log scaling
measurement and recording of harvested forest products to obtain a volume
define log grading
a system classifying harvested forest products for quality and suitability for manufacture into wood products (quality check on each log)
5 different ways to scale a timber product with examples
- Piece count: small, like quanities (Xmas trees)
- stacked volume: firewood, shake/shingle blocks
- lank: rails, pilings-not common
- mass and kgs: weight converted to solid wood volume **most common
- unit of solid wood converted to m3 AKA stick scaling-scaler physically measuring, using conversions
why is scaling and log grading needed?
to derive accurate volume for business transactions and get stumpage charges
what does a timber mark contain?
royalty rate, log exportability, identity of mark holder, area of origin
what is stick scaling
measuring and grading each log
what is weight scaling
weigh each load, establish relationship between volume and weight for each species
5 different ways in which quantity of log product recovery(grade) is affected?
fibre seperation perpendicular to growth rings(check)
fibre seperation between growth rings(shake)
bark seams
sweep, crook and pistol grip
rot, holes, char, missing wood
5 different ways in which quality of log product recovery (grade) is affected?
twist(spiral grain)
size of knots
types of knots: tight or loose, sound or rotten
distribution of knots
insect/worm holes
compression wood (leaning tree affects other trees growth-this is what gives Hw low value)
Grading Codes
- premium saw log
- saw log that doesnt make premium saw log(all other saw logs)
- lumber reject (usually used for pulp 25c/m)
Z. <50% firmwood by volume - undersized
2 main ramifications of not accounting for waste and residue volumes
- government loses money, paying lower stumpage, less wood going over scale
- potential over cutting
Main purpose of waste and residue assessment
To bill licensees monetarily for unreserved timber, whether standing or felled, that was not removed from the cutting authority area, and which meets or exceeds timber merchantability specifications.
What policy change caused a shift in the main purpose of waste and residue assessments in recent years?
“take or pay”
Legislation changed, not illegal to cut timber, but have to pay for it.
only stuff you havent stated up front is what you’re billed for
What 2 factors caused the take or pay policy
- Require licensees to recover volumes to economic margins but not beyond
- A: not an ecologically sound policy. removed all CWD
B: minimize site disturbance/degredation
what are the interior merchantability specifications?what were they previously called?
by species-all timber within merchantable specifications not excluded from harvesting by documentations.
previously called Utilization Standards
Define unavoidable waste
waste that is inaccessible or physically obstructed; could not be felled, bucked, or removed due to safety or environmental considerations (eg: log wedged between couple boulders)
NET merchantable volume AKA:
piece size
stand tables =
stock tables=
stand tables: stems/ha
stock tables: volume
Main product milled at ATCO?
veneer-Fd, sx, Lw
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Define simple random sampling</p>
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in choosing a sample of n sampling units(plots), every possible combination of n units should have an equal chance of selection. This happens by ensuring that the selction of sample unit or plot is completely independent from the selection of other sample units or plots.</p>
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Define stratified random sampling</p>
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population broken up into strata. each type of strata is then randomly sampled and the type estimates are combined to give the population estimates. This type of sampling is statistically preferable, but is sometimes not well suited to gathering all the additional info needed.</p>
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Define systematic sampling</p>
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units or plots are selected according to some pre determined sampling pattern. An element of randomness maybe incorporated into the sampling by the random selection of the starting point of the pattern. Stratification process could be used in a similar manner as in stratified random sampling.</p>
<p>
| Aside from timber, what are some other forest values which are becoming more commonly inventoried?</p>
forest health surveys fish/wildlife water resources vegetation road conditions recreation first nations claims archeological info/overviews visuals/esthetics carbon sequestration
steps in scaling:
truck rolls in.
truck goes over scale.
apply conv. factor to appropriate species to get weight and volume.
Random number generator determines if it needs to be stick scaled.
If not, truck rolls through, unloads.
If needs to be stick scaled, truck unloads and load gets measured.
Truck weighs in at empty, trucker signs documentation
What were the following species at ATCO used for?
Hw, Cw, Pl, Pw, Py, Bg, Sx, Fd, Lw
Hw, Pl, Py, Bg: pulp, saw logs
Cw: saw logs, shake, post and rail, poles
Pw: specialty, some pulp
Sx, Fd, Lw: veneer, if too big or too sm`all gets traded out.
ATCO steps of processing:
Fd: timber framers and log home builders. Takes a while to build a full load, buyers are super picky. Ship with veneer logs, get guys in yard to look at it rather than sorting it at the block.
PROCESSING:
Debarker produces hogfuel which produces energy
Cut to 8’ lengths, cookies are used as chips
Loaded into the wet room(makes softer, easier to peel)
Loaded into peeler
Peeler stage: landscape tie drops
peeled material rolls down line, gets cut into 8’ sheets, bad stuff is in smaller sections(some used, some not and is chipped)
