Subject: A Guide to Estimating Logging Costs
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A Guide to Estimating Logging Costs

in the Pacific Northwest (PNW)

Portland, OR, USA

January 1997

Table of contents:

1.        Introduction

2.          Disclaimer

3.         Logging cost estimation - users guide

4.         Machine description

5.         Definitions and assumptions

5.1       Time availability

5.2       Cost categories

5.3       Cost items

Ownership costs

Operating costs

Auxiliary (overhead) costs

5.4       Ownership period, residual value and repair reserve - criteria

5.5       Production units

5.6       Tree size

5.7 Harvest prescription

5.8       Yarding distance

5.9       Terrain class

5.10    Wages and benefits

5.11    Manual falling

5.12    Cable harvesting accessories

6.         Acknowledgments

Appendices (Logging Cost Estimates)

Tab 1   Common Factors
Tab 2   Cable yarding                - 40’ tower with stroke delimber
Tab 3   Cable yarding                - 40’ tower with manual delimbing
Tab 4   Cable yarding                - 50’ swing yarder
Tab 5   Cable yarding                - 70’ tower with stroke delimber
Tab 6   Cable yarding                - 70’ tower with manual delimbing
Tab 7   Cut-to-length harvesting
Tab 8   Helicopter yarding         - non pre-bunching
Tab 9   Helicopter yarding         - pre-bunching
Tab 10 Shovel logging
Tab 11 Skidder yarding             - wheel skidders with feller buncher
Tab 12 Skidder yarding             - wheel skidders with manual falling/delimbing
Tab 13 Skidder yarding             - track skidders with feller buncher
Tab 14 Skidder yarding             - track skidders with manual falling/delimbing

Introduction

The Oregon Department of Forestry (ODF) and Federal Bureau of Land Management (BLM) enlisted the World Forest Institute (WEl) to develop an up-to-date method of estimating typical harvesting costs for a range of common logging conditions. Both agencies, as public forest managers, have an obligation to ensure that standing timber is sold for a fair market value (or accredited for market value in land exchanges). The cost of logging needs to be estimated as a component of determining the market value of standing timber.

As the appraisal process is generally conducted prior to the sale and harvest of any particular parcel of timber (or exchange of land), details such as the purchaser, logging system and specific machine combination are not necessarily known at the time of appraisal.

This guide to estimating logging costs is designed for the purposes of appraising timber sales and combines a cost analysis of owning and operating the various machines commonly used for logging in the PNW with typical production rates given a typical range of site and stand variables. It thus represents the costs associated with common industry practice rather than the exact make-up of any single side. It is recognized that, in practice, the logging system actually used depends largely upon machine availability and that logging systems are generally designed to provide maximum flexibility for a variety of logging conditions rather than best suited to the job currently at hand.

The guide is also designed to provide simple and practical use in the field. Appraisers with a sound understanding of local stand and site conditions can use the guide to estimate logging costs for an individual site without having to undertake complex calculations or input additional detailed data.

Although aimed primarily at logging operations in public forests, it will also provide a usefUl resource for the private sector in analyzing operational costs and bid preparation. Appraisers and planners may use the guideline to compare the cost of particular logging systems for a given timber sale and to consider the impact on logging cost (and ultimately stumpage value) of planning options such as sale layout (e.g. roading and reserve design) and bid requirements (e.g. specifying the logging system).

Common industry practice and typical production rates were established following interviews with a variety of logging contractors, industry representatives, machinery manufacturers and sales representatives, industry consultants and others.

Due to difficulties in obtaining detailed cost data through direct survey, the likely machine costs and a range of production rates have been used to enable estimation of logging costs.

The guide does not attempt to estimate production for a particular logging operation, but

rather provides a range of po.ssible production rates (based on estimates by logging compani es) from which a user with field experience is able to select the most appropriate production leveL

The cost estimations included are “on-truck” only and do not include the cost of additional works, such as road construction or silvicultural/rehabilitation treatment, normally not required as part of the logging operation. Allowances for investment risk and profit margin have not been included. In addition, the guide is not intended fbr direct use in contract or rate negotiations, although they may be used to assist operators in calculating their individual operating costs.

2.        Disclaimer

While the cost and production data contained within this guide is intended to reasonably represent typical logging operations in the PNW, it may not accurately reflect any specific logging operation. As such, this guide should not be used to determine the exact cost of an individual logging operation.

3.            Logging cost estimation users guide

3.1       General

This guideline to estimating the cost of logging in the PNW is designed to provide

flexibility in use in the field and the opportunity for specific manual adjustment where

required.

The ability to manually adjust the base data and assumptions made provides the user with some flexibility to reflect individual circumstance, although as most appraisals occur prior to the bidding process, the guideline is aimed at providing the user with a range of typical logging costs for each common yarding system, assuming the given average tree sizes.

The guideline does not attempt to estimate production, but provides an estimate of logging costs under various yarding systems for a range of typical daily production. Field experience can then be used to refine the logging cost estimate according to an estimated specific level of average daily production, or the mid point of the typical production range may be selected as a representative figure where only a general approximation of the logging cost is required.

3.2       Data update

It is recommended that a master copy be kept for reference and to provide a base for future updates and refinements of the cost and production data. Working copies of the guideline may then be used by appraisers and planners and adjusted/refined to suite local practices an

Updates of machine ownership and operating costs are recommended to be carried out on a regular basis (yearly) in order to provide the most accurate and current reflection of logging costs. Similarly, it is advised that some resources be devoted on a regular basis to verifying likely production ranges for selected yarding systems and identifying additional factors which significantly influence production (e.g. account for regional differences within the PNW).

3.3       Guideline format

The guideline itself is composed of a series of connecting (linked) worksheets (spreadsheets) which are programmed using simple formula and linkages to adjust automatically when manual base data adjustments are made (hence the need to store an original master copy as a reference).

·   File structure

Within the main directory are the foliowing general files:

Main directory: Yardsyst, including:

Common.xls      - details common costs and assumptions (Common Factors spreadsheet)

Definit.doc - details of definitions and criteria for cost/production items

The set of spreadsheets are divided according to the yarding system, as follows:

Cable (cable yarding);

-40 ‘tower

40’tower, stroke delimber (files with name ending _ 40D)

40’tower, manual delimbing (files with name ending  _40M)

- SO ‘swyar, 50’ swing yarder (files with name ending  _50S)

-70 ‘tower

70’tower, stroke delimber (files with name ending  _70D)

70’tower, manual delimbing (files with name ending  _70M)

CTL; cut-to-length system (files with name ending  _CTL)

Helicop (helicopter yarding);

- Hel_Ma, non pre-bunching (files with name ending __HMA)

- Hel_Pb, pro-bunching with harvester (files with name ending HPB)

Shovel; shovel logging (files with name ending  _SHY)

Tireskid, wheel skidder

FB_tirsk~ wheel skidder, feller buncher (files with name ending EWS)

MA_tirsk: wheel skidder, manual falling/delimbing (files with name ending

_MWS)

Trkskid, track type skidder

FB_trksk: track skidder, feller buncher (files with name ending  _ETS)

MA_trksk: track skidder, manual failing/delimbing (files with name ending

_MTS)

Worksheet structure

There are five individual spreadsheets for each yarding alternative analyzed, as follows:

a) Common Factors

All common costs and assumptions, i.e. those factors common to more than one machine (e.g. interest rate, wages, insurance and maintenance criteria). Manual adjustments within this file will automatically recalculate all other relevant linked files.

b) Mach_file ending

This file contains one spreadsheet per machine and describes the calculation for the total cost (ownership and operating) for each individual machine assumed as a common component of that particular yarding system.

Costs have been calculated for selected models only within each machine type. Each spreadsheet contains additional columns where additional models may be added to increase the sample size or where the guideline user wishes to include a specific machine model.

Capital costs are based on the respective dealer’s list price only. This cost does not account for specific differences in machine quality, design and productivity.

c) Site_file ending

This shows the summary of the individual machine costs for that yarding system plus the auxiliary costs, resulting in a total US$/month figure for that operation (1 “side”).

____

A variation of +/- 10% is also automatically calculated to allow for additional influences on production not identified within this process (if required). In such case, criteria for the adoption of either the lower or the higher logging cost estimate should be identified and stated by the user.

d) Prod_mts

This spreadsheet contains the range of estimated production levels for the yarding system given the assumed forest and site variables. These estimates were established through a survey of selected logging industry.

e) Lgct_file ending

This file displays the calculated range of estimated logging costs in both table and chart format, allowing an estimate of the cost of the logging operation in US$/Mbf for a given production level.

It is the responsibility of the user to select the appropriate production level and therefore estimate the logging cost for each site. Extensive field experience and a working knowledge of logging production is recommended to achieve the most representative estimate of the likely logging cost for a given site

Step 1.             Install program diskette and enter main file

Step 2.             Select the appropriate yarding system from within the main file

Step 3.             Check assumptions within Common Factors spreadsheet (use default data unless adjustment is required to suit specific conditions).

Step 4.             Cheek assumptions within Machine Costs spreadsheet (use default data unless adjustment is required to suit specific conditions).

Step 5.             Check assumptions within Common Factors spreadsheet (use default data unless adjustment is required to suit specific conditions).

Step 6.             Check assumptions within Total Site Cost spreadsheet (use default data unless adjustment is required to suit specific conditions).

- Ensure equipment cost matches the total cost stated within each

Machine Cost spreadsheet.

- Adjust auxiliary costs if necessary within Total Site Cost

spreadsheet.

Step 7.              Estimate average daily production in truck loads (select appropriate truck load size).

Step 8.              Use the Logging Cost spreadsheet or the Range of Logging Cost chart to estimate the typical logging cost (in US$/MBF on truck) for the selected level of production.

Note:    Field appraisers may simply use the Range of Logging Cost chart for the appropriate yarding system to estimate an average logging cost during field appraisal, having been previously familiarized with the above workings of the guideline.

The results were not presented in $/cubic units due to the variable conversion factors for different log sizes.

4.         Machine description

The following table describes the individual machines used as a basis for estimating total site costs and production ranges. Machine types, set-up configuration and accessories reflect common industry practice in the PNW.

Machine Type

Description

Shovel Loader

Excavator base with raised cab and heel logging boom

Wheel Skidder

Rubber tire skidder with grapple

Track Skidder

Track skidder with grapple.

40’ Tower Yarder

Approx. 40’ trailer mounted, 4 drum drum (including strawline) tower yarder with skyline (slackline) and small motorized carriage/chokers. Capable of full lift and lateral yarding.

50’ Swing Yarder

Approx. 50’ track mounted, full interlocking 4 drum  (including strawline) swing yarder with running skyline and mechanical slack pulling carriage/chokers. Capable of full lift and lateral yarding

70’ Tower Yarder

Approx. 70’ track mounted, 5 drum (including strawline) tower yarder with skyline (slackline) and large motorized carriage/chokers. Capable of full lift and lateral yarding.

Harvester

Track or tire harvester with harvesting head. Capable of  felling, delimbing and bucking.

Forwarder

Tire forwarder with grapple log loader.

Feller Buncher

Track feller buncher with felling head.

Helicopter Approx.

11,500 certified pound lift capacity (assumed as  equivalent to twin rotor Vertol 107-11).

Log Delimber

Stroke delimber on excavator base.

Log Loader

Excavator base with raised cab and heel logging boom

Note:      Although other machine types are used by some logging contractors, the above machine types and configurations are those most commonly used for logging in the PNW. Where other machines are used and the cost structure/production range cannot be equated to any of the above machines, specific adjustments are required by the user for accurate logging cost estimates.

5. Definitions and assumptions

5.1        Time availability

Scheduled days per year

Available calendar days per year, total of 365 days, less Saturdays, Sundays and public holidays; i.e. 365 total available days - (2x52 Saturdays and Sundays) - (6 holidays) = 255 available calendar days per year.

Operational availability

Scheduled days less interruptions due to bad weather, fire restrictions, site set up and equipment mobilization;

Description of lost days

Shovel/Skidder systems

Cable/CTL

logging

Short term bad weather up to 3 days)

Compensated during week ends

Compensated during week ends

Longer - term bad weather and agency restrictions - not able to compensate

53

13

Moving equipment (one day every 2 months)

6

6

Between jobs - lost days

10

10

Fire restrictions

6

6

Total

75

35

Net (paid) hours/day

Assumed to be 8.5 hours/day for all logging systems except for CTL (9.0 hours/day) and helicopter (8.0 hours/day).

As average net hours/day for helicopter yarding can vary significantly, manual adjustments can be made within the Total Site Cost worksheet of the Helicopter Yarding Guide.

Mechanical availability

This makes allowance for machine breakdown (days when the operator is present and working conditions are suitable but machine breakdown results in operational downtime). This factor is higher for more reliable “static” equipment (e.g. cable yarders) and lower for “mobile” in-forest, heavily worked equipment (e.g. skidders).

Month

Considered to be 1/12 of the year. It does not exactly represent the costs of anymonth, but represents an average for all months, over the full year.

5.2     Cost categories

Common costs

Costs common to all or several machines (e.g. fuel price, insurance rates, interest rates, wages). Includes all costs which can follow a common assumption and thus stated as a common cost. This allows a more accurate comparison of the cost of running different machines and the generation of hypothetical “what if ?,, scenarios. It also facilitates more efficient update of the base data within the guide.

Machine costs

All costs associated with a specific machine, including:

Ownership costs: costs of owning the machine and usually not related to the level of activity (e.g. capital cost, depreciation, insurance); and

Operational costs: costs variable according to the level of production (e.g. fuel, tires, repairs).

Auxiliary (overhead) costs

Costs for operating a logging site which can not be associated with an individual machine

(e.g. administration, supervision, fire truck, office support, crew trailer, etc.) but are

essential in any logging operation.

Total site cost

Sum of individual machine cost and auxiliary costs. Represents the total cost of running the logging operation.

5.3  Cost items

Ownership costs

Type of Cost

Definition/Description

Source

Purchase
Price

Delivered new equipment with most common options/alterations.
Whether the machine is new or used is irrelevant in this case as the monthly cost is based on an average between aequisition and resale throughout the ownership period of the machine.

Price list from regional dealers

Average
Annual
Investment

Represents an average of the investment throughout the period of ownership. Calculated as follows: (N+1)/(2N)
x Delivered Price, being N the years of ownership. This is done to level out the capital cost independently of it being the first or the last year of the ownership period.

Calculated

Insurance

Insurance rate for the equipment stated as a yearly % of the Average Annual Investment.
Assumed to be: 3% (in-woods equipment), 2% (on landing equipment) per year.

Contractors

Personal property tax

Normally stated as a % depreciated value of each machine asset. Variable by county/state and so not included in costings. Provision to add manually within the Common Factors worksheet.

Contractors

Residual Value

Assumed to be trade-in value at replacement. Variable by machine type and function.

Dealers Contractors

Depreciation

Straight line depreciation over the ownership period. Represents the machine self pay-back distributed evenly during the working life.

Calculated

Interest over capital

Cost of immobilizing the capital. This is not the profit of the operation but the opportunity cost of the capital investment; i.e. the potential yield of the capital if it were not immobilized in logging equipment.

Calculated

Operating costs

Type of Cost

Definition/Description

Source

Repair Reserve

Represents an average cost of repairs during the ownership period of the equipment (including parts and labor). Repair costs generally increase with machine age, however the repair reserve assumes that the total repair cost is spread equally over the ownership period. The repair reserve is proportional both to the investment and to the working hours per year.

Dealers
Literature
Contractors

Fuel

Estimated using the “Cost Guide for Empirical Appraisals”- USDA (Revision 12, November 1983 guidelines). Fuel consumption is estimated based on horsepower (flywheel) rating (multiplied by 65% to adjust to intermittent use at median RPM) and checked with dealer estimates for verification.
Fuel Consumption in gallons per hour = 0.05137 x Rated flywheel horsepower.(^1.01265)

USDA
flywheel horsepower (dealers)

Lub, filters
and hydraulic

Expressed as a % of fuel cost per month. Assumed that
15% of the fuel cost (including labor cost).
Recommended by USDA (above reference) at 7% fuel
cost (excluding filter and labor).

USDA
Dealers
Contractor

Tires

Tires cost is considered for wheel skidders and forwarders due to relatively intensive tire wear for these machines. The cost of new tires are depreciated uniformly during the expected working life.

Dealers

Under-carrriage (track),

Track cost is considered for track skidders and shovel loggers. The maintenance cost for the undercarriage is estimated separately, following the guidelines described in the “Caterpillar Performance Handbook”, Edition 26, page 17-30 (e.g. for track skidders the Basic Factor
= 5.0, using moderate conditions of impact and abrasives (multipliers I=0.2, A=0.2, Z=0.5))

Dealers

Lines

For cable logging, the line (wire rope/cable) replacement is considered as a separate item, warranting a specific replacement reserve (US$/operating hour).

Dealers Contractors

Operator wage

Represents the total cost to the employer, not the net received by the employee; i.e. all inclusive (hiring and training costs, wages, overheads, etc.) and spread over the average employment period.

Oregon
Assoc.
Loggers

Auxiliary (overhead) costs

Individual auxiliary costs are detailed within the Total Site Cost worksheet for each yarding system analyzed (except for helicopter yarding where the overheads are included in the hourly cost for the helicopter).

The following criteria were adopted for the reserve machinery and administrative components of the auxiliary cost:

Reserve machinery

It is common for many logging operations to include a reserve machine (usually an older D5/D6 size crawler tractor) which operates relatively few hours per month mostly as a reserve machine and in site preparation/restoration. This machine costs less to own and operate than a regular machine.

Yarding system

Auxiliary Machine

40’tower

Yes

50’swing yarder

Yes

70’tower

Yes

Shovel

No

CTL

Yes

Tire Skidder

Yes

Track Skidder

No

Note:    Such a reserve machine is less commonly associated with track skidder and shovel yarding systems and was thus not included in the cost analysis for these systems.

· Administrative costs

Administrative costs associated with running a small office include: legal/accountancy, phone/fax., electricity, staff, rent etc.

It was assumed that on average, each logging operation consists of two “sides”, thus the cost to each side is a proportion of the total calculated administrative cost, depending on size and yarding system. The following table outlines the proportion of the total calculated administrative cost allocated to each side:

Yarding System 40’tower

SSingle-Side share of  total calc. adm. cost

33%

50’swing yarder

50%

70’tower

50%

Shovel

33%

CTL

50%

Tire Skidder

50%

Track Skidder

50%

Ownership period is estimated taking into consideration the residual value and the repair reserve. The period should reflect the actual useful life of the machine and not necessarily the tax related depreciation period. Longer ownership periods generally result in tradeoffs such as reduced residual value and increased repair reserve. The ownership period in years is a factor of the expected ownership period and will vary accordingly.

For most machines, the assumed period is approximately 7,000 - 12,000 hrs. The larger (50 - 70’) self mounted cable yarders have considerably longer ownership periods (18,000 hrs.) compared to most smaller (40’) trailer mounted cable yarders.

Residual value is estimated taking into consideration the machine function, level of technology (likelihood of being made obsolete), and level of commonness. It reflects the trade-in value and not the book value.

Repair reserve is proportional to both the investment and the working hour per year. It is stated primarily as % of a new machine (NM) per 1,000 hours of operation (%NM 1,000 hr), providing an estimate of the % of the investment for each 1,000 hrs. of work.

It can be also stated as % of the investment over the life span (ownership period) (%NM

Life Span), i.e. the total of the repair reserve accumulated over the ownership period.

Usually machines require between 1/3 to 1/2 of the original investment in maintenance.

The value is then converted to US$/hour.

5.5 Production units

The basic unit for production is a truck load, assumed to be 55,000 lb. by weight but

variable according to log size (volume). Estimated for each assumed age class as follows:

·     4,800 Mbf for mature logs (100 yrs.)
·     4,000 Mbf for private forest (45 yrs.)
·     3,700 for thinnings (40 yrs.)
·     3,200 for thinnings (30 yrs.)  (assuming 16’ short log length scale)

Where: - One cubic meter (m3) is equivalent to 35.31 cubic feet.

- One cubic foot is equivalent to 3.5 Bft for thinnings and 5.5 Bft for mature

timber.

- One m3 is approximately equivalent to 124 Bft for thinnings and 194 Bft for

mature wood (Loren Kellogg, OSU).

Note:

·    Production estimates are based on the production of the “side” as a whole, rather than on individual machine production. The critical component of the side’s production is assumed to be the yarding operation and, under normal circumstances, falling, delimbing/processing and loading do not restrict production levels (i.e. at least match the production of the yarding process).

·    It is assumed that the crew is adequately trained, the machines perform to the assumed level of uptime (see Common Factors worksheet) and the weather is regular for the season.

5.6 Tree size

Assumed as follows:

Size Class

Volume/tree

DBH

Typical Age  (Years)

Commercial Height (approx.)

Thinning*

70 Bft

9”

30

16’*2logs=32’

Thinning

130 Bft

12”

40

16’*3logs=48’

Mature rivate *

250 Bft

18”

45

16’* 4 logs = 64’

Mature

900Bft

28”

100

16’*7logs=112’

Note:    * tree sizes relevant to selected yarding systems only (i.e. not modeled for all yarding systems analyzed).

5.7 Harvest prescription

Assumed as follows:

Prescription

Typical  Age

Stand Volume

Canopy Removal

Comments

Thinning *

30 yrs.

4,500 Bft/ac

30%

Selective harvest

Thinning

.40 yrs.

7,000 Bft/ac

30%

Selective harvest

Regen Cut provate

45 yrs.

35,000 Bft/ac

90-95%

Typical “industrial clear cut

Partial cut

100 yrs.

20,000 Bft/ac

50%

Retain 15-18 trees/ac

Regen cut

100 yrs.

50,000 Bft/ac

70-90%

Retain <6 trees/ac

Note:    * prescriptions relevant to selected yarding systems only (i.e. not modeled for all yarding systems analyzed).

5.8 Yarding distance - External

Assumed as follows:

Yarding Distance Category

Distance (1-way)

Jusitification

Short

400 ft

Common shovel logging distance

Medium

800 ft

Common PNW yarding distance

Long

1500 ft

Typical cable yarding treshold

5.9 Terrain class

Assumed as follows:

Slope Classes

Grade

Criteria

Aerial yarding system

Helicopter/cable

Ground yarding system

tire

Ground yarding system

track

Flat

0-30%

Normal operational limit (tire machines)

Uncommon*

Yes

Yes

Medium

30-50.

Normal operational limit (track machines)

Yes

No

Yes

Steep

50%+

Traditional aerial yarding terrain

Yes

No

No

* aerial yarding may be used on flat terrain where certain environmental and other planning constraints need to be met.

5.10 Wages and benefits

Assumed wage classes include:

Description of Activity

Wage
(net US$/hr)

Example

Predominantly manual labor

12.00

Choker setter, chaser

Predominantly machine operation

15.00

Operator: feller buncher, tower

note: The net (or take-home) wage includes typical over-time costs.

Overheads and benefits considered above the net hourly wage include the following:

Item

%

Workers Compensation Insurance

28.0

Social Security Tax

7.5

State Unemployment  Tax

3.0

Federal Unemployment Tax

1.0

Health & Life Insurance

2.0

Vacation

1.0

Others: personal protection equip., hiring costs, training, etc

5.0

Total

47.5

Note:    Workers Compensation rate is based on an estimated average. Actual rates will vary between companies depending on operation size, level of mechanization and safety performance record.

5.11 Manual Falling

The number of fallers required for each yarding system is a function of the operation performed.

For the purposes of the analysis and reflecting common practice, the following number of fallers per side were assumed:

Type of operation

Logging System

Track/tire skidder

50’swing yarder’

70’tower

40’tower

Shovel logging

Manual Failing

3.5 fallers

3.0 fallers

Manual Failing and Delimbing

2.0 fallers

1.5 fallers

Note:    Falling was assumed (and is commonly) to be carried out on a sub-contract basis.

5.12 Cable harvesting accessories

The carriage and lines of a cable system are significant cost hems. Depreciation and maintenance/repair of the carriage and lines are considered as separate cost items, according to the following cost schedules:

Carriage:

Cable yarding System

Carriage type

Carriage Investment

US$

Carriage
maintenance

US$/hr

Carriage
depreciation

US$/hour

Rigging&
Chokers

US$

40’tower

Motor.

34,000

5.00

3.96

15,000

50’ SY

Mech.

15,000

1.00

1.80

25,000

70’tower

Motor.

100,000

5.00

12.00

25,000

Lines:

Cable Yarding System

Repair Reserve for lines
US$/hr of operation

40’ tower

5.00

50’swing yarder

8.00

70’tower

8.00

6.         Acknowledgments

The World Forest Institute wishes to thank the many people within various sectors of the forest industry who contributed their time and knowledge to the compilation of this guide to estimating logging costs. In particular, we wish to thank those loggers and logging equipment dealer representatives who provided invaluable advice and assistance.