cost

Objective:

Is to determine the costs of various logging systems that could be used to log this sale in the Washougal Watershed. This information will be used in conjunction with results of PLANS to determine a feasible harvest plan that maximizes production and profit while minimizing the impact on the environment.

To meet these goals several cable yarding systems will be analyzed for various settings and harvest prescriptions. The Skyap97 cable yarding cost appraisal program is used for determining cable yarding costs. Various yarding cycle equations for crawler and rubber tired skidders will be examined to determine tractor logging costs.

Results:
We chose to go with the Thunderbird TTY6170 yarder. The TTY6170 with a 70 foot tower provides more lift and using central landing will produces more per day then the other yarders analyzed.

Thunderbird TTY6170, 70 ft. Tower $589000

Table 1. Move In Move Out Costs

YEAR	1998	2028
Move In Move out Cost (40 miles one way)	$3542

Table 2. South Unit

YEAR	1998	2028
Total Harvest Volume (MBF)	1974	4511.6
Total Harvest (Acres)	53.1	53.1
Cut Volume per acre (MBF)	37.175	85.0
Average log volume (MBF)	0.070	0.368
Average net payload (lbs.)	2800	1000
Total number of sky roads	41	41
Average Yarding Distance (ft.)	650	650
Average Lateral Yarding Distance (ft.)	31	31
Estimated Daily Harvest (MBF/8 hrs)	22.190	73.652
Estimated Days to Harvest Unit	88.95	61.26
Total Cost per MBF	$89.20	$34.72
Timber Cutting Cost per MBF	$17.00	$14.50
Loading Cost per MBF	$19.75	$ 6.92
Logging Cost per MBF	$125.95	$56.14

Availability of adequate stumps for tailholds may present problems in logging this unit in 1998. Multiple stumps will have to be used to overcome this when adequate stumps are not available. Alternatively a mobile tailhold may be placed on the opposite ridge. The small estimated payloads, limited lateral yarding, and ample deflection combined with a skillful crew will reduce the occurrence of stump pull.

Table 3. North West Unit

YEAR	1998	2028
Total Harvest Volume (MBF)	1283	1932
Total Harvest (Acres)	34.5	34.5
Cut Volume per acre (MBF)	37.19	56.0
Average log volume (MBF)	0.120	0.2
Average net payload (lbs.)	3600	7000
Total number of sky roads	31	31
Average Yarding Distance (ft.)	650	650
Average Lateral Yarding Distance (ft.)	31	31
Estimated Daily Harvest (MBF/8 hrs)	30.22	48.51
Estimated Days to Harvest Unit	42.45	39.80
Total Cost per MBF	$73.27	$46.21
Timber Cutting Cost per MBF	$17.00	$14.50
Loading Cost per MBF	$14.90	$10.30
Logging Cost per MBF	$105.17	$71.01

Table 4. North Unit

YEAR	1998	2028
Total Harvest Volume (MBF)	907	1366.4
Total Harvest (Acres)	24.4	24.4
Cut Volume per acre (MBF)	37.17	56.0
Average log volume (MBF)	0.120	.20
Average net payload (lbs.)	3600	7000
Total number of sky roads	22	22
Average Yarding Distance (ft.)	660	660
Average Lateral Yarding Distance (ft.)	31	31
Estimated Daily Harvest (MBF/8 hrs)	30.058	48.33
Estimated Days to Harvest Unit	30.17	28.77
Total Cost per MBF	$70.93	$ 74.83
Timber Cutting Cost per MBF	$17.00	$14.50
Loading Cost per MBF	$15.00	$10.35
Logging Cost per MBF	$106.83	$72.36

Table 5. Tractor Unit

YEAR	1998	2028
Total Harvest Volume (MBF)	2306	2955
Total Harvest (Acres)	73.2	73.2
Cut Volume per acre (MBF)	31.5	40.37
Average log volume (MBF)	.110	.160
Average net payload (lbs.)	5500	8000
Average Yarding Distance (ft.)	310	300
Average Lateral Yarding Distance (ft.)	10	10
Estimated Daily Harvest (MBF/8 hrs)	40.00	50.00
Estimated Days to Harvest Unit(2 machines)	57.65	59.1
Total Cost per MBF	$25.52	$20.43
Total Cost/MBF include move in & out	$26.48	$21.18
Timber Cutting Cost per MBF	$16.00	$13.50
Loading Cost per MBF	$15.75	$13.60
Logging Cost per MBF	$58.23	$48.28

The Harvest area was divided into four units, three cable unit South, Northwest, North, and one tractor unit. The cable units were analyzed using the Skyap97 program to determine yarding costs and production. Timber cutting, tractor yarding, and loading costs are estimated using personal experience, conversations with contractors, and values from the U.S. Forest Service Region 6 Logging Guide, Revision 21, 3/97 (LG).

Labor cost for timber cutting was assumed to be $300 per 7 hour day, based on $47.12 from the cost guide. So it is assumed the cutting will be contracted by the MBF, for example cutting the South Unit was estimated at $17/MBF using estimates of 142 trees/acre and 0.24MBF/tree from the stand data, and the assumption the fallers would fell approximately 72 trees per day (0.24 x 72 x $17 = $293.76).

The loading cost was assumed to be at least $425 per day, and increases as production increases to $500 per day, these values were from Terry Clarke logging contractor. For the tractor unit loading included a chaser at $18.12/hr (L.G.), plus $4/hr saw allowance (8 x $22.12 = $177).

Skidding production was estimated using these formulas T₁ = 0.93 + 0.0066D + 0.152S + 0.0069V + 0.10N and T₂ = 0.016L + 0.00127u, where T₁ is skidding cycle, T₂ is winching cycle, D is yarding distance, S is slope, L is winching distance,V is turn volume, u is log volume, and N is number of chokers. This formula is from the FE341 Timber Harvesting class notes and yielded reasonable results.

Two skidding machines are used, two CAT D6H crawlers or CAT D6 and aCAT 518 rubber tire skidder are two possible skidding combinations. Table 5. Values are derived from the CAT Handbook and LG.

Table 6. Tractor Costs

Costs per Hour	Cat D6	CAT 518
Cost	$232,750	$112,550
Horsepower	165	130
Operator	$26.10	$26.10
Chokers and drumline	$1.45	$1.45
Fuel	$5.83	$4.59
Under carriage / Tires	$8.80	$1.75
Overhead	$18.62	$9.00
Repair Reserve	$9.31	$4.50
Misc.	$4.00	$4.00
Total Cost per Hour	$75.00	$52.00
Total Cost per 8 Hours	$600.88	$419.12

Yarders:

For analysis we have chosen these three yarders to be examined:

Koller 501 trailer mount : A thinning yarder (See Figure 1.) with an external yarding distance (EYD) of 1450 ft. The Koller 501 does not have a strawline so it is limited to uphill yarding, and a short downhill yarding of probably less than 350 ft.

Figure 1. The Koller 501 trailer mount yarder

Thunderbird TSY6255 Swing Yarder: This yarder is quick to move and rig up, requiring only 3 guylines it is great for continuous landings. The Thunderbird TSY6255 is capable of uphill, downhill, shotgun, hi-lead, standing skyline, and running skyline systems. It will have an EYD 2300 ft.

Thunderbird TTY6170 Yarder: Three drum machine with a 70 ft. tower and EYD of 2000 ft. This is the yarder selected to harvest the three cable units. This is a mobile yarder requiring 6 guylines.

Further Analysis:

Sky Appraisal

Using Skyap97 found at U:\FE_444\ENG\skyap97

Then double-clic either Skyapccf.exe or Skyapmbf.exe

Cable Yarders used for cost analysis:

Table 7. Thinning Yarder

Make

Koller

Model

501 Trlr Mount

Tower (ft.)

Weight (lbs.)

H.P

112

Cost

$143,000.00

Carriage

Weight (lbs.)

1200

H.P.

Cost

$ 33,600.00

Radio

Standard

Cost

$ 5,917.00

Mainline

1800 ft.

1/2 in.

Strawline

Haulback

2900 ft.

7/16 in.

Slackpulling

Skyline

1600 ft.

3/4 in.

Tong Line

150 ft.

5/8 in.

Total wire Rope Costs per MBF

$ 3.88

Forest Operating Hours Per Year

1800

Choker Size

20 ft.

1/2 in.

Lifetime

900 hrs.

$60.48 ea.

Guylines

145 ft

3/4 in.

Cost

$2417

Per hour

$ 0.34

Yarding Crew

Total Yarding Labor Cost Per Hour

$ 86.27

Operating Costs Per MBF at 24.87 MBF/day

$40.38

Table 8. Swing Yarder

Make

Thunderbird

Model

TSY6255

Tower (ft.)

Carriage

Weight (lbs.)

115,000

H.P

430

Cost

$609,375.00

Tbird MSP

Weight (lbs.)

600

H.P.

Cost

$7,335.00

Radio

Standard

Cost

$5,917.00

Mainline

2300 ft.

7/8 in.

Strawline

4600 ft.

3/8 in.

Haulback

4600 ft.

5/8 in.

Slackpulling

2300 ft.

7/8 in.

Skyline

0 ft.

in.

Tong Line

125 ft.

5/8 in.

Total wire Rope Costs per MBF

$ 3.88

Forest Operating Hours Per Year

1800

Choker

20 ft.

5/8 in.

Lifetime

1200 hrs.

$64.80

Guylines

125 ft.

1 1/8 in.

Cost

$3009

Per Hour

$0.42

Yarding Crew

Total Yarding Labor Cost Per Hour

$122.51

Operating Costs per MBF Prod. 32.53 MBF/day

$61.59

Table 9. Mobile Tower

Make

Thunderbird

Model

TTY6170SSK

Tower (ft.)

Carriage

Weight (lbs.)

H.P.

430

Cost

$589,000.00

TBirdS-35DL

Weight (lbs.)

2200

H.P.

Cost

$16,000.00

Radio

Standard

Cost

$5,917.00

Mainline

2700 ft.

3/4 in.

Strawline

4500 ft.

3/8 in.

Haulback

4400 ft.

3/4 in.

Slackpulling

4500 ft.

3/8 in.

Skyline

2000 ft.

1 1/8 in.

Tong Line

ft.

5/8 in.

Total wire Rope Costs per MBF

$ 10.45

Forest Operating Hours Per Year

1800

Choker

20 ft.

5/8 in.

Lifetime

1200 hrs.

$81.00

Guylines

220 ft.

7/8 in.

Cost

$6355

Per Hour

$0.88

Yarding Crew

Total Yarding Labor Cost Per Hour

$122.51

Operating Costs per MBF Prod. 32.53 MBF/day

$48.02

Table 10. Small Tower

Make

Thunderbird

Model

TMY40

Tower (ft.)

Carriage

Weight (lbs.)

31,600

H.P.

175

Cost

$321,750.00

Weight (lbs.)

H.P.

Cost

$ 0.00

Radio

Standard

Cost

$5,917.00

Mainline

2000 ft.

1/2 in.

Strawline

4000 ft.

1/4 in.

Haulback

4200 ft.

7/16 in.

Slackpulling

0 ft.

0 in.

Skyline

2000 ft.

3/4 in.

Tong Line

125 ft.

5/8 in.

Total wire Rope Costs per MBF

$ 6.63

Forest Operating Hours Per Year

1800

Choker Size

20 ft.

1/2 in.

Lifetime

900 hrs.

$60.48

Yarding Crew

Total Yarding Labor Cost Per Hour

$104.39

Operating Costs per MBF Prod. 25.77/day

$52.89

Comparable costs for felling, yarding, and loading (stump to truck costs) are calculated using regression equations from Forest Service appraisal data and computer simulation studies. (Chris B. LeDoux 1986; Western Journal of Applied Forestry April, 1986; p. 19-22). For cost comparison with Skyap97 see Table 11.

Using these equations in conjunction with Skyap97, PLANS, cruise data and input from logging professionals a preliminary harvest cost analysis can be accomplished.

Table 11. Costing Comparison

Year	Unit	DBH	SYD	VOAC	$/MCF	C.F.	$/MBF	1998 $	Skyap97	Diff
1998	South	17.10	650	37.18	$279.75	4.61	$60.67	$86.50	$125.95	31%
2028	South	23.54	650	84.96	$201.10	5.34	$37.64	$53.66	$56.14	4.4%
1998	NW	15.40	650	37.19	$321.36	4.38	$73.40	$104.65	$105.17	0.5%
2028	NW	20.00	650	56.00	$229.14	4.97	$46.11	$65.74	$71.01	7.4%
1998	North	15.40	650	37.17	$321.36	4.38	$73.40	$104.65	$106.83	2.0%
2028	North	20.00	650	56.00	$229.14	4.97	$46.11	$65.74	$72.36	9.1%

Table 11 compares Skyap97 cost estimates with cost generated using the regression equations from the Forest Service. The equations give stump to truck cost in 1986 dollars per thousand cubic feet ($/MCF), these are converted to dollars per thousand board feet ($/MBF) using the conversion factor (C.F.). Finally $/MBF is converted to 1998 dollars using 1998 $ = ($/MBF)*(1 + I)ⁿ letting n = 12 and i = 3% years. The final three columns compare the costs and the percent difference of the values.

Figure 2. Eight Stump Nightmare

Assume angle at Block 1 = 40 ° and the angle at Block 2 = 20 °, then

at Block 1: 2T + 2Tcos(20) = 130 kips T = 33.5 kips

at Block 2: 2T = 67 kips 67 = 2T₂cos(10) T₂ = 34.0 kips

Then stumps A,B,C,and D must have diameters > 18" or Diameters > 16.3" and guyed back to stumps a,,b,c, and d respectively.

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