9. Attachment 9_Timber Cruising in the Pacific Northwest (no exercises).pdf

Basic Cruiser Training Workbook

June 1, 2017

Timber Cruising in the Pacific Northwest

United States Department of Agriculture Forest Service Pacific Northwest Region

R6-NR-TM-TP-21-97

Region 6 Forest Service

U.S. Department of Agriculture

Timber Cruising in the

Pacific Northwest

Timber Cruising in the Pacific Northwest i

Objectives

Learn, Practice, & Apply

1. Cruising process and procedures.

2. Terminology associated with cruising.

3. Proper techniques for taking tree measurements.

4. Characteristics used to identify tree species.

5. Evaluate sawlog, green bio convertible (Grn Bio CV)/ non-sawlog and cull products.

6. Identify tree defects and make defect deductions.

7. Region 6 common sampling methods.

8. Data collection and documentation.

9. Written test.

Timber Cruising in the Pacific Northwest ii

Preface

This workbook provides instruction on the basic cruise measurements, as well as five primary cruising methods currently used in Region 6. It’s designed to supplement instructor lecture and field application.

This course stresses correct individual tree measurements, and a working knowledge of 100%, Sample Tree, 3P, Fixed Plot, and Point Sample cruise methods. This workbook will be used to develop consistency for timber cruising across Region 6.

There are four levels of certification for cruisers.

Qualified Cruiser: The qualified cruiser is responsible for applying a variety of volume determination techniques. As a minimum, the cruiser must be proficient in cruising fundamentals such as tree measurements, species identification, defect recognition and determination, quality determination, map reading and compass use, traversing, photo interpretation, working knowledge of the commonly used cruise systems and be able to interpret and follow a timber cruise plan.

Advanced Cruiser: The advanced cruiser is fully qualified to perform measurements, train prospective cruisers, conduct all types of timber cruises, and design and implement cruises.

Experience, technical interest, training ability, and initiative characterize this classification.

Check Cruiser: The check cruiser is responsible for check cruising, cruiser training and conducting evaluations to recommend certification of qualified and advanced cruisers. The check cruiser maintains an active field check cruising program, retains records of individual cruisers and sale check cruise results. The check cruiser inspects timber cruises and recommends acceptance or identifies deficiencies and corrective actions for them. Additionally, they are responsible for establishing Forest certification test areas.

Master Cruiser: The master cruiser is certified by the Regional Forester and serves as a representative for cruising and coordinates the Regional quality control program.

Timber Cruising in the Pacific Northwest iii

Introduction

Timber cruising is the process of tree selection and measurement that determines the volume and value of usable wood in standing trees.

Region 6 has approved two log rules for determining volumes; Smalian Cubic Foot Log Rule and the Scribner Decimal C Log Rule. The National Cruise Program calculates volume in cubic feet for the Smalian Cubic Foot Log Rule and in board feet for the Scribner Decimal C Log Rule.

National Forests in Washington and Oregon sell timber to private corporations and individuals. In order to receive a fair value for the timber, cruisers must collect accurate information.

National Forests have plans that furnish direction on how lands will be managed to provide opportunities for recreation, timber harvest, grazing, and a wide variety of other uses. The goals set in these plans determine how much, where, and when timber may be removed.

Ranger Districts further refine plans that schedule timber harvest over a period of several years. These plans estimate the volume of wood that will be removed and are valuable to private industry for planning future mill operations.

Before the proposed harvest, Categorical Exclusions (CE), detailed Environmental Analysis (EA) or Environmental Impact Statement (EIS) are prepared. People within and from outside the Forest Service work together during the analysis and timber sale planning process and the results of these documents discloses effects the planned sale will have on the environment, and establishes objectives for long-range management.

Silviculturists work closely with other specialists and write prescriptions and tree marking guides that achieve these objectives.

Sale Preparation Teams lay out units and designate trees to be cut. Timber cruisers, as part of the team, determine the Volume and Value of wood to be removed, and in many cases, act as both marker and cruiser.

Region 6 sells two types of sales: Tree Measurement and Scaled. Tree Measurement Sales (TMS) are sales in which the volume is determined by cruising and is paid for prior to removing the trees. Scaled sales are sales in which the volume offered for sale is determined by cruising but payment is made after trees are removed, hauled to the mill and scaled for actual volume.

All timber sales, land exchanges, and trespass cruises shall be cruised by certified cruisers.

Data collected by cruisers, such as average tree size and volume per acre, is used in the Timber Sale Appraisal, which determines the price of the timber offered for sale. Errors in data collection will affect volume estimates, which affect the payment received by the government from timber sales, either scaled or tree measurement sales.

Demand for timber resources within our National Forests has created the potential for conflicts.

Accurate timber volume estimates can reduce potential conflict and are important in monitoring Forest Plans, insuring adequate log accountability, and receiving full value for what is sold.

Timber Cruising in the Pacific Northwest iv

Cruise Planning

Prepare a cruise plan for each timber sale (FSM 2442.04c, 2442.2 and FSH 2409.12). At a minimum, the cruise plan must cover:

1. A definition of the sample population

2. Sample methods and intensity for each population.

3. Product merchantability specifications.

4. Sale area maps.

5. Silviculture guides, when required.

The cruise plan provides instruction for the cruising crew. It will cover all pertinent cruising elements for the timber sale involved. Consider the checklist below when preparing a cruise plan:

1. Silviculture prescriptions and/or marking guides.

2. Sampling, or cruise design, include cruise method(s) and intensity (ies) by unit and the analysis leading to the design. In cruise design, consider size and shape of units, payment units, right-of-way, landing clearings, riparian zones, wildlife trees, and so forth. List sample groups, units and strata.

3. Sale/Cruise number.

4. List Unit of Measure: Cubic or Scribner

5. Product merchantability specifications (may tie into species and relative values).

6. Sale area working maps, including sample plot/point location maps.

7. Strata and unit information – including acres.

8. Safety items specific to the sale.

9. Special measurement techniques: for example, visible defect, Mirage Points (points close to boundaries), and rounding rules, i.e., carry all mathematical calculations a minimum of five (5) characters to right of decimal point before final rounding. When final rounding, use one character to the right of the desired accuracy. When rounding to two decimal places evaluate the third, i.e., round .36542 to .37 or round .36442 to .36.

10. How to handle hidden defect and breakage (Hidden defect and breakage is a percent of volume loss applied to the sale as a whole to account for unseen defect and anticipated breakage during logging. Hidden defect is defect in the inner portion of the tree, having no visible indicators;

therefore, no deductions can be made by the cruiser. The breakage results in volume loss that occurs during falling, bucking, yarding, loading and all other normal damage.)

Timber Cruising in the Pacific Northwest v

11. Which volume equations will be used, stem profile or 616?

12. Will form class need to be determined? Using what method?

13. In an area-based cruise, describe how the unit acreages will be determined, traversed, or GPS’d, and how the stations will be monumented.

14. Describe how sample points and sample trees will be marked and monumented (ribbon color, plot stakes, paint color).

15. What will be the plot location controls – how will distances between plots be measured? Will cruise lines be referenced to unit boundary traverse stations or a base line? How to locate the first point in a unit? How will the location of Sample Tree (STR)/Probability Proportional to Prediction (3P) sample trees be documented – map, photo?

16. Log grading (product designation): Grade 1 = Sawlog Grade 8 = Grn Bio CV/Non-Sawlog Grade 9 = Cull.

17. How are cut and leave trees marked? See Regional/Forest Accountability Action Plan.

18. How will tree heights be measured and recorded – Total Height or Merchantable Height in Feet?

How to differentiate these two on cruise cards. What is the top DIB to cruise to – by species?

19. Special/local defect (instructions) guidelines, i.e., worm holes, char, etc.

20. If a 3P cruise is planned, how will KPI’s be estimated – gross or net? What aids will be given to the cruisers to help estimate KPI’s?

21. If a Sample Tree cruise is planned, how will sample trees be selected? Will a random number list be provided – by species?

22. What sample group and species codes will be used?

23. How will data be recorded? Cards or Field Data Recorders (FDR)? If FDR, cruise plan must reference cruisers names to initials for check cruising purposes.

Timber Cruising in the Pacific Northwest vi

Data Recording

An integral part of good sampling and cruising techniques is accurate and legible data recording.

Mistakes made at this point are often difficult to detect and correct in the office. All header information must be filled in completely!

There are two types of data recording: card entry and electronic handheld data recorders.

Region 6 uses two types of cards to record cruise data in the field.

1. R6 FScruiser TREE CARD (R6-FS-2400-405)

2. R6 FScruiser 3P TREE CARD (R6-FS-2400-404)

R6 FScruiser TREE CARDS are used for all cruises except 3P.

Timber Cruising in the Pacific Northwest vii

Heading

Forest and District are entered as two digit codes.

Cruiser name shall be filled out in full, not by using initials. Only certified cruisers shall be listed.

Date is the day(s) the cruise data was collected.

Cruise number shall be filled out.

Sale Number shall be filled out. (This is not applicable on cruise cards dated 11/05 or newer.)

Sale Name is to be completed in full.

Strata Number will come from the cruise plan.

Unit Number must be filled in for all sampling methods.

Point/Plot Number is required for area based cruises. Enter only one point/plot per card.

Sighting Point refers to the location on the tree where the determination of In or Out trees is made.

This is always DBH. (This is not applicable on cruise cards dated 11/05 or newer.)

BAF (Basal Area Factor) is filled in when point sampling.

Plot Size is filled in when plot sampling.

Timber Cruising in the Pacific Northwest viii

Tree Information

Tree # shall be entered on measured points/plots and individual trees. On points/plots, each cut tree, regardless of count or measure, shall be numbered.

CNT/MEAS is a one-position alpha entry. C for count and M for measure.

SG is alphanumeric and is required in most cases. Blank (no entry) is a valid code. Only two characters allowed. This is applicable on cruise cards dated 11/05 or newer. SLUPCY (EtAl) is used on cards prior to 11/05.

Species Code is alpha-numeric and is required. Can have up to four characters.

DBH is required and is entered in tenths of an inch.

Tree Count is no longer required on PCM (POINT, COUNT, MEASURE), FCM (FIXED, COUNT, MEASURE) and P3P (POINT 3P). When using tree cards, tree count will be left blank for each tree, regardless of count or measure. Each tree must be documented separately. DO NOT record more than one tree on each line.

For height measurements, Stem Profile Equations and 616 Equations require total height or merchantable height in feet.

Total Height is measured and recorded to the nearest foot.

Merchantable Height in Feet is measured and recorded to the nearest foot.

Top DIB is optional when cruising to a total height. If left blank, the contract minimum specified in the cruise plan will be used. Top DIB is required when cruising to merchantable height in feet.

Defect Percent is applied to the entire tree. Defect in this field and in log defect fields are cumulative.

This entry is not commonly used. (This is not applicable on cruise cards dated 11/05 or newer.)

Form Class is optional. If left blank, the default Form Class will be listed in the cruise plan.

Log Grade Position: The top row is used to enter the grade (product designation) of each log by position. Logs are graded in maximum 16-foot segments.

Defect deductions are also made by log position. Deductions must be made on visible indicators and are entered as a % of log volume to be deducted. Logs are defected in maximum 16-foot segments.

Remarks – include cruisers initials for every tree.

Timber Cruising in the Pacific Northwest ix

R6 FScruiser 3P Tree Cards are used exclusively for 3P cruises.

Tree Number is assigned to each cruise tree.

KPI (volume estimate) is the cruiser’s estimated volume.

3P Code: Inapplicable with National Cruise Software Version 2 and later.

Timber Cruising in the Pacific Northwest x

Editing

Editing is an important part of data collection. No matter how accurately the measurements were taken, if data was recorded incorrectly or omitted, then, at the very least, you have biased the cruise.

A first field edit should be done before leaving the point/plot or cruise tree to insure all necessary data has been recorded. A second field edit should be done at the end of the day to assure you did not lose any field cards.

An office edit of the field cards must be made by an experienced cruiser prior to data entry and then after data entry to check for input errors. This is especially true if the data entry is done by someone with no knowledge of cruising.

Module I Page 1

Module I – Tree Measurement

The foundation for all consistent cruise results is accurate measurements. Sloppy measurements will not balance out. There is always bias when taking poor measurements.

Bias is a systematic error. Measurement bias occurs when an instrument is out of adjustment and inaccurately measures each sample by a fixed amount. Estimation bias occurs when a volume estimator consistently over or under estimates actual tree volumes. Selection bias occurs when selected trees, plots or points over or under represent a timber condition.

Methods of Measurement

Region 6 uses two units of measurement: Cubic and Scribner.

Cubic volume is determined using the Smalian Cubic Formula.

The Smalian Cubic Formula calculates volume in units known as cubic feet. The dimensions of a cubic foot are 12 inches by 12 inches by 12 inches.

Volumes are calculated using the length of the log, the small end diameter and the large end diameter. Volumes are calculated for each log segment.

26”

12” 12”

12” 16.5’

Cubic Foot

30”

Module I Page 2

The Cruise Processing program computes volume for each log segment, adds those together, giving the total volume of the tree.

Module I Page 3

Methods of Measurement Continued

Scribner volume is determined using the Scribner Decimal C Log Rule.

The Scribner Decimal C Log Rule calculates volume in units known as board feet. The dimensions of a board foot are 1 inch by 12 inches by 12 inches.

Volumes are derived from a table showing an estimate of the amount of lumber a log of a given length and diameter can produce. This table uses the small end diameter and a scaling cylinder, which is an imaginary cylinder extending through the log length with a diameter equal to the small end.

Volumes are calculated for each segment.

26”

12”

1” 12” 16’ 6”

Board Foot

Scaling Cylinder

26”

Module I Page 4

The Cruise Processing program computes volume for each log segment, adds those together, giving the total volume of the tree.

Module I Page 5

Volume Determinations

Two types of volume equations are currently used: 616 (Behr’s Hyperbole) and Stem Profile (Ingy and Flewelling). Both of these equations can be used to determine cubic and scribner volumes.

Three measurements are required to calculate volume when using 616 equations: DBH, Height and Form Class.

Only two measurements are required to calculate volume when using Stem Profile Equations: DBH and Height.

DBH and height measurements are the same regardless of the unit of measure or what cruise method is used.

With these measurements, the cruise program can determine number of logs, log lengths, log end diameters and calculate tree volumes.

Tree taper is the progressive change in diameter as you move along the bole of the tree. Taper is different on each tree, but a standard guideline when the amount of taper is unknown would be 1 inch per 8 feet on all species except Western larch, then use 1 inch per 16 feet.

Cruising Instruments

Commonly used equipment for timber cruising is:

Spiegel Relaskop Data Recorders Clinometer Cruise Cards Prisms Telescoping Poles Compass Hatchet/Axe Diameter Tape Binoculars Loggers Tape Calculators Laser Scopes Aerial Photo Scales Tatum Aids Signal Mirror

Cell Phone

Safety items to consider while cruising are:

1. Radio

2. Hard hat

3. 8” high, non-skid soled boots

4. Long sleeve shirts

5. 1st Aid/bee sting kits

6. Safety glasses

7. Gloves

8. High visibility vest

9. Review JHA

10. Cell Phone

Module I Page 6

Diameter

Diameters are normally taken at 4.5 feet above the natural forest floor, on the high side of the tree.

This point is known as Diameter at Breast Height or DBH.

Diameter tapes must be perpendicular to the tree bole. Some conditions causing incorrect DBH measurements include: twisted tapes, sag in tapes, abnormalities at DBH or reading the tape upside down.

DBH

4.5 ft.

Occasionally debris will obstruct the base of the tree. DBH measurements are taken from the normal natural forest floor or duff layer. Disregard piled debris such as dirt, rocks, limbs or logs.

4.5 ft. Debris

Natural Forest Floor

Module I Page 7

Diameter tapes convert circumference to diameter measurements.

Numbers on the tape should be read right side up to avoid reading errors.

Diameters are rounded down to the nearest 1/10th inch.

12 13 12 13 12 13

12.5” 12.59”=12.5” 12.6”

Right hand and left hand tapes are available.

Left Handed (counter clockwise) Right Handed (clockwise)

Module I Page 8

Leaning Tree DBH is measured perpendicular (right angle) to the tree bole.

4.5’

Tree with Forks Above DBH are measured as One tree.

Trees with Forks Below DBH are measured as Two trees.

Module I Page 9

Trees grown together are measured as two trees. This is indicated by a bark seam above and below

DBH.

4.5”

Measure as close as possible to the DBH and adjust for each tree.

Cankers or burls located at DBH can be measured using two methods.

Method A: Measure as close as Method B: Measure above and possible to DBH and below an equal adjust for taper. distance from DBH and average, providing there is no severe butt flair.

Module I Page 10

Severe catface and abnormal butt swell are measured above the swell while noting the height of that measurement.

Estimate the average taper in normal trees of comparable size or use the standard taper rule, and apply taper rate to approximate DBH.

Catface or scar will be measured by extending the tape to reflect the natural rounded shape of the tree.

Module I Page 11

Trees growing on objects (rocks, logs) are measured from the root crown.

Split or shattered trees are measured as close to DBH as possible then adjusted for taper.

Measure Here (above shatter)

Module I Page 12

Abnormal Diameters Class Problems

No. 1 Instructions: Draw location of measure point(s).

Make notes to help describe measurements.

a.)

b.)

c.)

d.)

e.)

f.)

g.)

Module I Page 13

Heights

Two types of height measurements can be taken: Total Tree Height, which is recommended and Merchantable Height in Feet.

1. Total Tree Height--- measurements are taken from stump height to the tip of the leader and recorded in feet.

2. Merchantable Height in Feet---measurements are taken from stump height to a specified top or contract minimum diameter and recorded in feet.

Stump height is 12” on the high side from the natural forest floor.

Module I Page 14

Total Tree Height

Total tree height is measured from the stump to the tip of the leader and recorded to the nearest foot.

When Total Height cruising, a minimum Top Diameter Inside Bark (Top DIB) is not required.

Example 1: Standing trees

Module I Page 15

Example 2: Broken off trees – measure standing portion to the break, then measure portion on the ground from the break to the top of the tree and add together for total tree height.

B

Measured Height

Measure B C

Stump Height A

Module I Page 16

Merchantable Height in Feet (Specified Top)

Merchantable tree height is measured from stump height to a Specified Top Diameter or Contract Minimum Diameter and recorded in feet.

Top Diameter Inside Bark (Top DIB) must be recorded. This is the point on the bole where no more saw timber products are expected. See cruise plan for additional direction regarding multiple products.

Two factors influence the placement of this Top DIB.

1. Minimum Contract Diameters. (Example 1)

2. Specified Top. (Example 2)

Example 1: Minimum Contract Diameter

Module I Page 17

Example 2: Specified Top

a. Broken/missing top trees: Measure to the break and record height in feet and specified top DIB at this point. Disregard the break if it occurs above the minimum contract diameter.

Specified Top

Measured Height

Stump Height

b. Flat topped trees: Measure to the point where diameter is too small or too defective

(where no more merchantable products are expected) and recorded in feet.

Specified Top

Module I Page 18

Log Chart

The chart below is only used for determining the number of logs in a tree for grading and defecting purposes. Actual heights include trim allowance of .5 foot per log.

DO NOT use total heights when determining number of log positions, only use merchantable heights.

If the measured merchantable height exceeds the actual merchantable height by more than 2 feet, then an additional log position will require grading or defecting.

Log Chart(April, 2015)

Number of Logs

Actual Merchantable Height

(Top of Stump to Top of Log)

15 247

14 231

13 214

12 198

11 181

10 165

9 148

8 132

7 115

6 99

5 82

4 66

3 49

2 33

1 16

Module I Page 19

Forked Trees

Forked top trees are measured by two methods depending on the fork location.

1. Trees forked below DBH are measured as two trees.

Two Trees

2. Trees forked above DBH are measured as one tree. (Note:

there is no bark seam.)

One Tree

Measure dominant fork.

Snags and dead top trees are measured the same as live trees.

Module I Page 20

Relaskop Use

The Spiegel Relaskop is the primary measurement instrument in Region 6. This instrument may be used to obtain height and diameter measurements or measuring basal area. When measuring heights and diameters, the Relaskop does not adjust for slope distance. When measuring basal area, the Relaskop automatically adjusts for slope.

Relaskops have Percent (%), Topographic (T), and Degree (0) scales.

Relaskops can be read directly at 100’ (Percent - %) and 66’ (Topographic – T).

If heights are taken from other than these two horizontal distances, readings will require adjustments.

To do this, multiply your height reading by the height reading factor listed below.

♦ Plug tape into the side of the tree directly below the tip or leader of the tree.

♦ Measure out at least as far as the tree is tall.

Percent Scale (%) Topographic Scale (T)

Horizontal Distance Height Reading Factor Horizontal Distance Height Reading Factor 83' 0.83 33' 0.5 100' Read Direct (1.0) 66' Read Direct (1.0) 125' 1.25 99' 1.5 200' 2 132' 2

66’ Slope Correction Scale (Not found on all Relaskops)

Module I Page 21

When measuring height, the distance below and above horizontal needs to be accounted for.

It’s most preferred to read a negative number when sighting at stump height. This negative number is added to the positive reading at the top of the tree to get the height.

Sighting uphill at stump height will give positive readings. This positive number is subtracted from the positive reading at the top of the tree to get the height.

♦ Measure height from uphill or side hill whenever possible. No slope correction is needed when slopes are 5% or less.

Example 1: Stump height below sighting point (negative number).

A A = +75 B = -5 A – B = Height 75 – (-5) = 80’

+75

-5 B 1’ Stump

Example 2: Stump height above sighting point (positive reading).

A = +70 A B = +3 A – B = Height 70 – (+3) = 67’

+70

B 1’ stump +3

Module I Page 22

A correction must be made for any measured distance on slopes greater than 5%. The following example illustrates how to establish a known horizontal distance on slopes.

Slope = 48% Slope Adjustment Factor = 1.11

66.0’ (Horizontal)

C

A-B = 66.0’ (Slope Distance)

A to C = 73.26’ (Adjusted Slope Distance)

Procedure:

1. Measure out the appropriate desired distance (A-B).

2. Measure the slope using the Percent Scale (%). (Parallel to ground; eye height to eye height.)

3. Locate the corresponding slope adjustment factor from the chart in the Tatum Aid or

Training Workbook.

4. Multiply the desired distance (66 feet in this case) by the slope adjustment factor (1.11).

66’ ∗ 1.11 = 73.26’ (A to C)

73.26’ (Adjusted slope distance) on 48% slope equals 66’ horizontal distance, so you need to tape out an additional 7.26’.

Module I Page 23

Leaning Trees

Leaning trees should be measured at right angles to the lean. Trees that lean towards the cruiser will have a larger critical angle, thus resulting in a taller height measurement. Conversely, trees leaning away from the cruiser will have a smaller critical angle, resulting in a shorter height measurement.

Trees leaning 25% (about 15°) or more from vertical need a height adjustment.

Procedure: a. Measure vertical distance. (A to B)

b. Measure horizontal distance. (B to C)

c. Calculate correct height. (A to C)

100’

C 42’

A TO B (AB) = 100’ AC = 22 BCAB +

B TO C (BC) = 42’

A TO C (AC) =??? AC = '764,1'000,10 +

AC = 108’

Module I Page 24

Height Measurements Class Problem

No. 2

1. Region 6 currently utilizes two tree height measurement types. What are they? Describe briefly.

a.

b.

2. What are the heights of the leaning trees?

a.

b.

A A

150’ 112’

C 40’ C 30’ B B

Module I Page 25

Diameter Instruments

Relaskops and diameter tapes are used to take diameter measurements.

Diameters can be measured using various bar width combinations with the Relaskop. Diameters must be read at known horizontal distances.

Bar widths used for measuring diameters vary as the Relaskop is tipped up and down; only in this regard does it adjust for slope. When measuring heights, the Relaskop does not adjust for slope distance.

Bar Width Equivalents Horizontal Distance Pair of Large Bars Small Bars

33' 12" 2" 66' 24" 4" 99' 36" 6"

132' 48" 8"

Module I Page 26

Module I Page 30

Form Class

616 Volume Equations require Form Class (FC) to calculate top diameter of the first log. This directly affects the diameters of the remaining logs in the tree, which affects the volume of the whole tree.

Form Class is a ratio of the diameter inside bark (DIB) at the top of the first log to DBH. Form Class takes into account the taper of the first log, from diameter at breast height (DBH) to the top of the first log.

The more Form Class varies between trees within a species, the more samples will be needed. 25 – 30 samples are required per species across the sale area.

Small errors in DOB measurement can cause large differences in Form Class. There is approximately 2-3% volume difference between Form Classes.

Examples below show how slight differences in measurements can have large differences in Form Class.

Note difference between small and large DBH’s.

Example 1: Small Tree (14.2” DBH)

Relaskop Bar Measurements Actual Measurements 11.0” 11.5”

Form Class: 77 Form Class: 81

Example 2: Large Tree (40.0” DBH)

Relaskop Bar Measurements Actual Measurements 30.0” 30.5”

Form Class: 75 Form Class: 76

Module I Page 31

Top DIB can be determined two ways:

1. Measure directly - bark has been removed and the diameter is measured directly on the wood.

2. Apply a known Bark Thickness Ratio (BTR) - measure diameter with bark still on tree and apply a BTR.

Bark Thickness Ratio (BTR) is the ratio between diameter inside bark (DIB) and diameter outside bark (DOB) at top of the first log (DIB ÷ DOB).

Direct A Known BTR

Bark Thickness

.5” on one side = 1.0” total

DIB = 22.0” DOB = 23.0” (Diameter Outside Bark)

23.0” – 1.0” = 22.0” DIB

BTR =

DOB

DIB

BTR = 96.956.

"0.23 "0.22

DBH = 30.0” DBH = 30.0”

Example A: FC

DIB

=∗100 Example B: FC

DBH

BTRDOB

∗ 100

73100

=∗ 74100

96.23

Bark has been peeled off

Bark still on

Module I Page 32

There are three common methods for determining Form Class:

A. Direct B. Limiting Distance C. Bar Scale

A. Direct Method for Form Class

1. Measure DOB at the top of the first log with a diameter tape.

2. Determine DIB by either

a. measuring the bark thickness and subtract it from DOB to determine DIB or,

b. applying a BTR to the DOB which calculates the DIB,

3. Divide the DIB by the DBH, and multiply by 100 to calculate Form Class.

4. This can be done with the use of ladders on standing trees, or by measuring felled or wind thrown trees. This is an excellent way to obtain Form Class because all measurements are made directly.

FC = 100∗

Module I Page 33

B. Limiting Distance Method for Form Class

1. Measure DBH, rounding down to the nearest 1/10th inch.

2. Situate the zero end of your loggers tape at about your eye level and directly below the center of the tree at the top of the first log. Note: Project that center from the top of the first log vertically downward to eye level. Tape must be plugged in on the side of the tree, not the face of the tree.

3. After correctly positioning the zero end of your loggers tape, measure away from the tree (to the north, for example), until the scale of the Relaskop that comprises 40 BAF (or the appropriate smaller BAF on smaller trees) are the exact same width as the tree at the top of the first log’s outside bark. Then, without changing the distance between your head/eye and the tree, measure the distance from the zero end of your tape to your eye, to the nearest one hundredth of a foot and record it. The measured distance used must be horizontal distance. If the measured distance is more than 5% slope, it must be changed to horizontal distance before calculation. Then repeat this entire procedure to the west or east; 90 degrees from the first reading, as explained above.

4. After repeating the procedure in step 2 and 3, add both distances together and divide by two to average them.

5. Take the average distance calculated in step 4 and divide it by 1.375, which is the plot radius factor to the center of the tree for 40 BAF, or use the appropriate plot radius factor for the BAF being used. Plot radius factors are found on page 10 in the Tatum Aids.

♦ Carry mathematical calculations a minimum of five (5) characters to right of decimal point before rounding.

6. Multiply the result of step 5 by the specified BTR, to get the DIB at the top of the first log.

7. Divide the top DIB (result of step 6) by the DBH and multiple by 100 to get the Form Class.

Record both the DIB at the top of the first log and FC on the cruise card. Record DIB below the FC in the green comment area.

8. Limiting Distance Formula:

FC = 100∗

HeightBreastDiameter

RatioThicknessBark TreeofcentertoFactorRadiusPlot

DistHorizontalAverage

Module I Page 34

C. Bar Scale Method for Form Class - Using the Relaskop

1. Measure DBH, rounding down to the nearest 1/10th inch.

2. Situate the zero end of your loggers tape at about your eye level and directly below the center of the tree at the top of the first log. Note: Project that center from the top of the first log vertically downward to eye level. Tape must be plugged in on the side of the tree, not the face of the tree.

3. Move back to a fixed distance with the loggers tape, i.e. 33’ or 66’ from the base of the tree.

Inside the Relaskop the scale between “a” and “b” is divided into 6 equal width bars (3 light and 3 dark). The projection of the distance “a” to “b” is equal to:

1 foot (each bar 2 inches) at horizontal distance of 33 feet 2 foot (each bar 4 inches) at horizontal distance of 66 feet

4. Sight through the Relaskop at top of the first log. The diameter outside the bark at this point can be measured using the scale bars between “a” and “b”. Measure from the left side of the scale to the right. The left side of the scale is placed on the left edge of the bole of the tree and the number of bars to the right is counted and the diameter is estimated to the nearest inch. This measurement becomes the DOB.

Sight from the direction that minimizes tree lean, slope, and brush; preferably a cardinal direction (north, south, east, west). Then repeat this procedure 90 degrees from the first reading. Then average these two readings for the average DOB.

5. The DOB is then multiplied by a specified BTR to establish the DIB at the top of the first log.

Record both the DIB at the top of the first log and FC on the cruise card. Record DIB below the FC in the green comment area.

6. The DIB is then divided by the DBH and multiplied by 100 to determine the Form Class.

7. Bar Scale Formula: FC = 100∗

DBH

BTRDOB

a b

Module II Page 37

Module II – Species and Product Designation

Species Identification

Tree characteristics to help determine species:

a. Bark color, pattern, and texture.

b. Tree form or shape.

c. Number of needles per fascicle.

d. Length and shape of needles.

e. Cone size and shape.

f. Geographic location.

Species identification is essential due to the different uses and values.

Species Delivered Log Price

Uses

Ponderosa pine $245.00/CCF $ 472.00/MBF molding, finished lumber Douglas-fir $199.00/CCF $ 383.00/MBF construction (lumber/plywood) White fir/Grand fir $187.00/CCF $ 360.00/MBF plywood core, construction Lodgepole pine Western red cedar

$187.00/CCF

$585.00/CCF

$ 360.00/MBF

$1125.00/MBF

studs, house logs, poles decks

Grn Bio CV/Non-sawlog $25.00/TON particle board, paper, hog fuel.

Module II Page 38

Product Designation “Grading”

During recent years, changes in resource management have brought about changes in the type of material that is available to harvest. Smaller size trees and changing markets have created some opportunities to improve our efficiency and accuracy in timber sale preparation. This will help to streamline the timber sale cruising and appraisal process.

Cruiser assigns one of three (3) “grades” to each log. Grade each log independently, without considering the grade of other logs in the tree. Logs are evaluated as they appear at the time they are cruised. DO NOT project to what they “might” be at the time of harvest.

Acceptable Grades are:

Grade 1 = Sawlog Logs that meet sawlog minimum specifications.

Grade 8 = Grn Bio CV/Non-sawlog Logs that do not meet sawlog minimum specifications are evaluated for Grn Bio CV/Non-sawlog specifications. Grade 9 = Cull N/A when Grn Bio CV/Non-sawlog products are included in the cruise.

Product Determination Procedures

1. Locate each 16’ log segment, including trim, in the tree by measuring height.

2. Grade each 16’ log segment. Segment lengths are the same for cubic and scribner.

3. Assume it is a sawlog product until proven otherwise.

4. Make deductions for any sawlog defects.

5. Grn Bio CV/Non-sawlog products are cruised for gross volume only. No deductions are made for defects on Grn Bio CV/Non-sawlog products.

Cruise for sawlog product (Grade 1) first. If sawlog defects exceed the maximum defect % allowed, the log becomes a Grn Bio CV/Non-sawlog product (Grade 8). When Grn Bio CV/Non-sawlog products are included in the cruise, product designation of cull (Grade 9) is inapplicable.

If Grn Bio CV/Non-sawlog products are not a cruise component, logs not meeting sawlog specifications will become cull (grade 9).

Merchantability Specifications

Maximum Defect Product Cubic Scribner Sawlog (Grade 1) 60% 66% Grn Bio CV/Non-sawlog (Grade 8) Cruise for gross volume only, no defect deductions.

Cull logs (Grade 9) N/A when Grn Bio CV/Non-sawlog products are included in the cruise.

Module II Page 39

Cubic

Grade 1 – Sawlog (all species) Grading Specifications

Logs shall be suitable for the production of lumber or veneer to an amount of not less than 40 percent of gross cubic foot volume and has a minimum Diameter Inside Bark of 5.0 inches at the small end.

Grade 8 – Grn Bio CV (all species) Grading Specifications

Logs not meeting the sawlog specifications will be evaluated using Grn Bio CV specifications.

Logs shall be suitable for the production of any product other than lumber or veneer and have a minimum Diameter Inside Bark of 2.0 inches at the small end. Grn Bio CV products will be cruised only for gross volume. No deductions are made for defects on Grn Bio CV products. Forests may set the minimum top DIB larger than 2”.

Grade 9 – Cull (all species)

Logs not meeting sawlog specifications. N/A when Grn Bio CV products are included in the cruise.

Module II Page 40

Scribner

Grade 1 – Sawlog (all species) Grading Specifications

Logs shall be suitable for the production of lumber or veneer to an amount of not less than 33.3 (34) percent of gross Scribner volume and has a minimum Diameter Inside Bark of 5.0 inches at the small end.

Grade 8 – Non-sawlog (all species) Grading Specifications

Logs not meeting the sawlog specifications will be evaluated using non-sawlog specifications.

Logs shall be suitable for the production of any product other than lumber or veneer and have a minimum Diameter Inside Bark of 2.0 inches at the small end. Non-sawlog products will be cruised only for gross volume. No deductions are made for defects on non-sawlog products. Forests may set the minimum top DIB larger than 2”.

Grade 9 – Cull (all species)

Logs not meeting sawlog specifications. N/A when non-sawlog products are included in the cruise.

Module III Page 43

Module III – Defect Recognition and Deductions

In Region 6, sawlog volume is sold on a basis of net volume; gross volume minus defect deductions establishes net volume.

In Region 6, Grn Bio CV/Non-sawlog volume is sold on a basis of gross volume.

Gross Volume = Net Volume (Gross and Net Volume are the same volume).

Sawlog:

♦ Deductions can be taken in one percent (1%) increments.

♦ Deductions are made for seen defect only.

♦ Deductions are applied to each log segment at the time they are cruised.

DO NOT project defect to what it “might” be at the time of harvest.

♦ Defect in even 2-foot multiples.

♦ Minimum merchantable length is six (6) feet.

♦ Refer to the cruise plan for minimum merchantable length.

Grn Bio CV/Non-sawlog:

♦ Grn Bio CV/Non-sawlog products are cruised for gross volume only. No deductions are made for defects on Grn Bio CV/Non-sawlog products.

♦ Refer to the cruise plan for minimum merchantable length.

Two major classifications of defect deductions are hidden and visible.

1. Hidden defects lack external indicators therefore the cruiser cannot make defect deductions. This, along with breakage (anticipated damage that occurs during felling, bucking, skidding and loading) is accounted for during the cruise input process.

2. Visible defect deductions are based on the existence of visible indicators; not hunches or feelings.

Portions of the tree that can be affected:

1. root and butt

2. heartwood or stem

3. sapwood or perimeter

Module III Page 44

Sources of Defects

There are two sources of defects: Natural and Logging/Mechanical.

1. Natural defects exist in the log before the tree is felled. These may include all kinds of rot, rotten knots, scars, fire scars, cat faces, lightning scars, massed grub worm holes, bark seams, forks, sap rot, crook and sweep.

2. Logging/mechanical defects are usually caused by machinery or skidded logs rubbing against the base of a tree during a previous logging operation. These defects can also be caused during felling and processing. This may include defects such as breaks, tractor damage, loading and unloading damage.

Defect indicators are visible abnormalities that need further investigation. Cruisers may or may not find defects associated with these indicators.

Examples of defect indicators include:

1. butt swell

2. sap rot

3. conks

4. crook

5. bark seams

6. catface

7. broken tops

8. sucker limbs

9. fire scars

10. insect damage

11. sweep

12. forks

Module III Page 45

Defect Categories

1. Sawlog defects - reduce the amount of lumber or veneer that can be manufactured from a log.

Types of defects include:

a. breaks – partial or complete break in a log

b. checks – internal or external cracks in the log

c. rots – decomposition of wood substance

d. crook – abrupt curve or bend in a log

e. sweep – gradual curve in a log

f. fire scars – injury caused by fire

g. frost cracks – cracks caused from contracting/expanding moisture in trees

h. lightning scars – deduct for any rot, weather checks or massed pitch

i. voids – no wood present

j. soft rots – rot not usable for any product

k. char – burned wood, charcoal

l. massed pitch – wood impregnated with pitch

m. metal objects—fencing, nails, railroad spikes, horseshoes

2. Grn Bio CV/Non-sawlog defects– no deductions are made for defects on Grn Bio CV/Non-sawlog products.

Module III Page 46

Cubic

Sawlogs are allowed a maximum of 60% product defect.

Sawlog

Log Break Non-sawlog

Log Break

60% Defect

Soft Rot

Grn Bio CV products will be cruised only for gross volume. No deductions are made for defects.

Net Cruise Volume equals Gross Cruise Volume

Grn Bio CV

Module III Page 47

Scribner

Sawlogs are allowed a maximum of 66% product defect.

Sawlog

Log Break Non-sawlog

66% Defect

Soft Rot

Scaling Cylinder

Non-sawlog products will be cruised only gross volume. No deductions are made for defects.

Net Cruise Volume equals Gross Cruise Volume

Module III Page 48

Defect Deduction Methods

When making defect deductions, the same process will be used regardless of the unit of measure, cubic or scribner.

• Length cut Defect in even 2 foot multiples

• Pie cut or percent Use when defect is confined to a face on the tree. For example:

• Use a fraction of the log - 1/8, 1/4, 1/3, 1/2

• Use a percentage of the log such 12%, 25%, 33%, 50%

• Percent - length cut Combination of percent and length. For example:

• Use a fraction of the log – 1/2 of 4 feet, 1/4 of 8 feet, 1/3 of 6 feet

• Use a percentage of the log - 50% of 4 feet, 25% of 8 feet, 33% of 6 feet

• Diameter deduction Use for perimeter defects May use in combination of percent deduction

Module III Page 49

Rots

Root rots spread underground and destroy the fine root system, which in turn, make trees susceptible to wind throw. Wind thrown trees, caused by root rot, are identified by nubbed off roots.

Wind Thrown Tree

Fine roots missing

Common Root Decays

a. Laminated root rot (Phellinius weirii/Poria werii)

b. Shoestring rot (Armillaria ostoyae)

c. White spongy rot (Fomes annosus)

Butt rot indicators (fruiting bodies/conks) occur near the tree base; sometimes attached. Butt swell often occurs, with volume loss normally limited to a portion of the butt log.

Swollen Butt

Fruiting Bodies (Conks)

Common Butt Decay

a. Velvet top or cow-pie (Phaeolus schweinitzii)

Module III Page 50

Heart rots affect the heartwood (dryer center portions) of the tree, rather that the moist sapwood. Age of the tree and location of conks can be a determining factor as to the extent of damage.

Common Heart Rots

a. White speck (Phellinus pini/Fomes pini)

b. Indian paint conk (Echinodontium tinctorium)

c. Quinine conk (Lariciformes/Fomes officinalis)

d. Sulfur conk (Laetiporus/Polyporus suphureus)

e. Yellow cap fungus (Pholiota adiposa)

f. Light brown cubical top rot (Fomitopsis cajenderi)

Module III Page 51

Sap rots affect the moist outer perimeter of the tree bole. Dead trees are the primary hosts.

Common Sap Rots

a. White pouch fungus (Cryptoporous/Polyporus volvatus)

b. Purple conk (Hirschioporus/Polyporus abietnum)

Module III Page 52

Basal/Trunk/Stem Injury Rots

Mechanical injuries often occur when a tree was younger and smaller, usually caused by machinery or skidded logs rubbing against the base of the tree during previous logging operations. Fungi rots are sometimes introduced through these injuries. Basal and trunk (stem) injuries are especially susceptible to fungi infection. The severity usually increases with age.

Basal/Trunk injuries appear similar to severe fire scars, with the absence of the char. Fungi rot is almost always associated when in contact with the ground on an old injury. Trunk injuries are not in contact with the ground.

Trunk Scar

Basal Scar

Fire scars appear to be more severe than they really are. Fire will often have a case hardening effect on the tree and limit rot.

Fire Scar

Module III Page 53

Deductions for fire scars, basal, and trunk injuries are made only if there is volume loss. For Scribner, only consider defect penetrating the scaling cylinder.

Cubic Scribner

Trunk Injury Trunk Injury

Lightning scars are a form of trunk injury that may have little or no deduction. Make deductions for rot, weather checks or massed pitch if necessary.

Cubic Scribner

Lightning Scar (Spiral)

Module III Page 54

Frost cracks occur when extremely low temperatures freeze and expand the moisture in trees. Species such as true firs with high moisture content are most susceptible. Defect deductions are made for frost cracks and will be more severe for multiple frost cracks.

Broken tops, unless recent, may have associated rot. Stem shatter or rot below the merchantable top should be deducted.

No deduction above log break

Deduct for shatter or rot

Module III Page 55

Forks caused from past injuries or genetics will have limited deductions made for the area immediately adjacent to the fork.

Sweep and Crook may require a volume deduction. Sweep is a gradual stem deflection and is less abrupt than crook. Deductions for sweep and crook are made for the void and the portion of the log that will not produce standard length lumber in the manufacturing process. Sweep and crook are defect deductions for sawlogs.

Log Log Break Break

15% of 8 feet = 8% 40% of 8 feet = 20%

8’ 8’

Log Log Break Break

Module III Page 56

Sawlog Defect Table in Percent

Length of Defect in Log (in feet) 1* 2 3* 4 5* 6 7* 8 9* 10 11* 12 13* 14 15* 16

5% 0 1 1 1 2 2 2 3 3 3 3 4 4 4 5 5 % 10% 1 1 2 3 3 4 4 5 6 6 7 8 8 9 9 10 15% 1 2 3 4 5 6 7 8 8 9 10 11 12 13 14 15

O 20% 1 3 4 5 6 8 9 10 11 13 14 15 16 18 19 20 F 25% 2 3 5 6 8 9 11 13 14 16 17 19 20 22 23 25 30% 2 4 6 8 9 11 13 15 17 19 21 23 24 26 28 30 L 35% 2 4 7 9 11 13 15 18 20 22 24 26 28 31 33 35 O 40% 3 5 8 10 13 15 18 20 23 25 28 30 33 35 38 40 G 45% 3 6 8 11 14 17 20 23 25 28 31 34 37 39 42 45 50% 3 6 9 13 16 19 22 25 28 31 34 38 41 44 47 50

A 55% 3 7 10 14 17 21 24 28 31 34 38 41 45 48 52 55 F 60% 4 8 11 15 19 23 26 30 34 38 41 45 49 53 56 60 F 65% 4 8 12 16 20 24 28 33 37 41 45 49 53 57 61 65 E 70% 4 9 13 18 22 26 31 35 39 44 48 53 57 61 66 70 C 75% 5 9 14 19 23 28 33 38 42 47 52 56 61 66 70 75 T 80% 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 E 85% 5 11 16 21 27 32 37 43 48 53 58 64 69 74 80 85 D 90% 6 11 17 23 28 34 39 45 51 56 62 68 73 79 84 90 95% 6 12 18 24 30 36 42 48 53 59 65 71 77 83 89 95 100% 6 13 19 25 31 38 44 50 56 63 69 75 81 88 94 100

*Odd lengths are not used for defecting purposes.

Find the length of your defect along the top row and then the percent of the length affected down the left side. Consider defect length in even 2-foot multiples for sawlogs. Use only for 16 foot logs.

For logs segments measuring 16 feet in length, each foot contain 6.25% of the total volume. This is determined using the following formula:

Example: Defect % per foot = (1/segment length)/ * 100 = (1/16) * 100 = 6.25% per foot.

Top log segment lengths can be shorter than 16 feet in length. For log segments measuring less than 16 feet, the same formula is used to determine defect percent per foot.

If the top log is 10 feet, defect % per foot would calculated as:

Example: Defect % per foot = (1/segment length)/ * 100 = (1/10) * 100 = 10% per foot.

Module III Page 57

Determining Saprot Loss

Consider the following:

1. Needle condition (dying, dead or missing).

2. Bark condition (tight, sloughing, missing).

3. Visible checks or indicators.

4. Sap conks present (age-new or old).

5. Chop to determine extent of decay.

Determine the average depth of decay and then double it, i.e., if you chop at four places and get depths totaling 8”, divide by 4, equaling 2” average defect depth. Double this 2” and find the 4” depth on the Cubic Perimeter Defecting Guide, with the appropriate small end diameter of the log.

CUBIC PERIMETER DEFECTING GUIDE (07/09)

(DEFECT PERCENT BASED ON 16’ LOG VOLUMES)

DEPTH OF DEFECT IN INCHES - 2 SIDES

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

5 31 57 75 S 6 27 50 72 M 7 25 44 62 74 A 8 22 40 57 70 L 9 19 37 52 65 77 L 10 18 33 48 60 71 11 - 12 16 30 43 55 63 72 E 13 - 14 14 26 38 49 58 65 72 N 15 - 16 12 23 34 43 52 61 69 73 D 17 - 18 11 21 30 39 48 54 62 68 75 19 - 20 10 19 27 35 44 51 57 64 69 74 D 21 - 23 9 17 25 32 39 46 52 58 64 68 73 I 24 - 26 8 15 22 29 35 41 47 53 58 63 67 72 74 A 27 - 29 7 13 20 26 32 38 43 48 53 57 62 66 70 74 76 M 30 - 32 6 12 18 24 29 34 39 44 49 53 57 61 65 69 72 75 E 33 - 35 6 11 17 22 27 32 36 41 45 50 53 57 61 64 68 71 74 76 T 36 - 38 5 10 15 20 25 29 34 38 42 46 50 54 57 61 64 67 70 73 75 E 39 - 41 5 10 14 19 23 27 31 35 40 43 47 50 54 57 60 63 66 69 72 74 R 42 - 44 4 9 13 17 22 26 30 33 37 40 44 48 51 54 57 60 63 65 68 71 73 75 45 - 47 4 8 12 16 20 24 28 31 35 38 41 45 48 51 54 57 60 62 65 68 70 72 74 75 48 - 50 4 8 12 15 19 22 26 30 33 36 39 42 45 48 51 54 57 59 62 64 67 69 71 73 75 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

DEPTH OF DEFECT IN INCHES - 2 SIDES

To use: Determine average depth of perimeter defect; double the defect for both sides; apply to defecting guide to determine defect percent. For sap rot, deduct the full percentage shown. For weather checks, deduct ½ the percent shown if straight and deduct the full percent if spiral.