1. (1) Introduction. The acceptable log scaling and grading standard for stumpage value areas 1, 2, 3, 4, 5, and 9 is the Scribner Decimal C log rule as described in the most current edition of the "Official Log Scaling and Grading Rules" developed and authored by the Northwest Log Rules Advisory Group. The acceptable log scaling standard for stumpage value areas 6 and 7 is the Scribner Decimal C log rule described in the most current edition of the "Eastside Log Scaling Handbook" as published by the Northwest Log Rules Advisory Group, except that timber harvested in stumpage value areas 6 and 7 must be scaled using the current regional taper rules at the point of origin.
2. (2) Special services scaling. Special services scaling as described in the "Official Log Scaling and Grading Rules" developed and authored by the Northwest Log Rules Advisory Group may not be used for tax reporting purposes without prior written approval of the department of revenue.

3. (3) Sample scaling. Sample scaling may not be used for tax reporting purposes without prior written approval of the department of revenue. To be approved, sample scaling must be in accordance with the following guidelines:

   1. (a) Sample selection, scaling, and grading must be conducted on a continuous basis as the unit is harvested.
   2. (b) The sample must be taken in such a manner to assure random, unbiased sample selection in accordance with accepted statistical tests of sampling.
   3. (c) The sample used to determine total volume, species, and quality of timber harvested for a given reporting period must have been taken during that period.
   4. (d) Sample frequency must be large enough to meet board foot variation accuracy limits of plus or minus two and five-tenths percent standard error at the ninety-five percent confidence level.
   5. (e) Harvesters, or a purchaser with an approved sample scaling method, must maintain sufficient supporting documentation to allow the department of revenue to verify source data, and test statistical reliability of sample scale systems.
   6. (f) Exceptions: Sampling designs and accuracy standards other than those described herein may only be used with the prior written approval of the department of revenue.

4. (4) Conversions to Scribner Decimal C Scale. The following definitions, tables, and conversion factors must be used in determining taxable volume for timber harvested that was not originally scaled by the Scribner Decimal C Log Rule. Conversion methods other than those listed are not to be used for tax reporting purposes without prior written approval of the department of revenue. Harvesters who wish to use a method of conversion other than those listed below must obtain written approval from the department of revenue before harvesting. Purchasers may obtain written approval of a sample scaling method from the department of revenue. The department will maintain a list of purchasers with an approved sample scaling method. A harvester may obtain this list and a summary of the approved method for specific purchasers from the department of revenue. If a harvester has not obtained approval of a sample scaling method before harvesting, the harvester may use a purchaser's approved sample scaling method. If the harvester, or purchaser, fails to use an approved sample scaling method or other method of conversion approved by these rules to set the purchase price, the department will establish its own method, as the circumstances require, to determine a reasonable estimate of the volume of timber sold.

   1. (a) Weight measurement. If the sole unit of measure used to set the purchase price for logs from harvest units was weight, and the harvester does not use an approved method of sample scaling to determine volume for the stumpage value tables, the following tables must be used for converting to Scribner Decimal C, if the harvest volume per species meets the definition listed in the table. If weight is the sole measure used for a harvest unit and the harvest volume per species does not meet the definition listed in the table below, the department will establish its own method, as the circumstances require, to determine a reasonable estimate of the volume of timber sold. Harvesters must keep records to substantiate the species and quality codes reported. For tax reporting purposes, a ton equals 2,000 pounds.

      (Stumpage Value Areas 1, 2, 3, 4, 5, & 9)board foot weight scale factors(tons/mbf)
      Species	Quality code
      		1
      Douglas-fir1		7.50
      Western Hemlock2		8.25
      Western Redcedar3		7.0
      Red Alder4		7.80
      Chipwood		9.0

      1	Includes Douglas-fir, Western Larch, Western White Pine and Sitka Spruce. Only for volume including less than 25% No. 2 sawmill or better log grades.
      2	Includes Western Hemlock, Mountain Hemlock, Pacific Silver Fir, Noble Fir, Grand Fir, Subalpine Fir, Lodgepole Pine and other conifers not separately designated. Pacific Silver Fir, Noble Fir, Grand Fir, and Subalpine Fir are all commonly referred to as "White Fir." Only for volume including less than 25% No. 2 sawmill or better log grades.
      3	Includes Alaska-cedar.
      4	Maple, Black Cottonwood and other hardwoods. Only for volume including less than 40% No. 3 sawmill or better log grades.

      (Stumpage Value Areas 6 & 7 )board foot weight scale factors(tons/mbf)
      Species	Quality code
      		1
      Ponderosa Pine1		6.50
      Douglas-fir 2		5.50
      Lodgepole Pine		6.0
      Western Hemlock 3		5.50
      Englemann Spruce		4.50
      Western Redcedar 4		4.50
      Chipwood		9.0
      Small Logs		6.50

      1	Only for volume with 10 or more logs 16 feet long per thousand board feet Scribner scale.
      2	Includes Western Larch.
      3	Includes Western Hemlock, Mountain Hemlock, Pacific Silver Fir, Noble Fir, Grand Fir, Subalpine Fir, and other conifers not separately designated. Pacific Silver Fir, Noble Fir, Grand Fir, and Subalpine Fir are all commonly referred to as "White Fir."
      4	Includes Alaska-cedar.

   2. (b) Cord measurement. For the purposes of converting cords into Scribner volume:

      1. (i) In stumpage value areas 1, 2, 3, 4, 5, and 9 logs with an average scaling diameter of 8 inches and larger must be converted to Scribner volume using 400 board feet per cord. Logs having an average scaling diameter of less than 8 inches must be converted to Scribner volume using 330 board feet per cord.
      2. (ii) In stumpage value areas 6 and 7 logs with an average scaling diameter of 8 inches and larger must be converted to Scribner volume using 470 board feet per cord. Logs having an average scaling diameter of less than 8 inches must be converted to Scribner volume using 390 board feet per cord.
      3. (iii) A cord of Western Redcedar shake or shingle blocks must be converted to Scribner volume using 600 board feet per cord.
      4. (iv) Firewood must be converted at a rate of 3 tons per cord.

   3. (c) Cants or lumber from portable mills. To convert from lumber tally to Scribner volume:

      1. (i) In stumpage value areas 1, 2, 3, 4, 5, and 9 multiply the lumber tally for the individual species by 75%, and round to the nearest one thousand board feet (MBF); or
      2. (ii) In stumpage value areas 6 and 7 multiply the lumber tally for the individual species by 88%, and round to the nearest one thousand board feet (MBF).
   4. (d) Log scale conversion. Timber harvested in stumpage value areas 1, 2, 3, 4, 5, and 9 and which has been scaled by methods and procedures published in the "Eastside Log Scaling Handbook" must have the volumes reported reduced by eighteen percent. Timber harvested in stumpage value areas 6 and 7 and which has been scaled by methods and procedures published in the "Official Log Scaling and Grading Rules" developed and authored by the Northwest log rules advisory group, must have the volumes reported increased by eighteen percent.

   5. (e) Timber pole and piling volume tables. Harvesters of poles must use the following tables to determine the Scribner board foot volume for each pole length and class:

      Total Scribner Board Foot VolumeStumpage Value Areas 1, 2, 3, 4, 5, and 9
      	Pole Class1	Piling Class2
      Length	H6	H5	H4	H3	H2	H1	1	2	3	4	5	6	7	9	10	A	B
      20							50	50	40	40	30	30	20	20	20	80	70
      25							60	60	50	50	40	40	30	30	30	100	90
      30							110	70	60	60	50	50	40	40		130	110
      35					160	160	130	100	80	80	60	60	50			130	110
      40			240	200	180	180	150	120	120	90	70	60				150	120
      45	380	340	340	280	230	230	190	150	120	120	90	90				150	120
      50	430	370	370	300	260	260	210	160	140	140	100					160	140
      55	470	410	410	330	280	280	230	180	150	150						180	150
      60	540	470	470	410	340	340	290	220	190	190						190	160
      65	610	520	520	420	380	380	320	260	210	210						210	180
      70	650	560	560	480	400	400	350	270	230	230						230	190
      75	700	600	600	520	520	520	440	290	250							230	200
      80	820	700	700	600	600	540	440	360	290							250	210
      85	910	800	800	660	660	660	570	490	360							260	210
      90	1080	930	930	820	820	690	590	490	400							260	220
      95	1170	1000	1000	870	870	750	640	540								290	240
      100	1190	1030	1030	900	900	760	660	550								310	250
      105	1310	1160	1160	1000	1000	860	740	610								330	270
      110	1370	1220	1220	1050	1050	910	780	650								380	300
      115	1440	1280	1280	1100	1100	960	860	680								400	310
      120	1660	1460	1460	1300	1300	1140	970	820								500	400
      125	1840	1600	1600	1410	1410	1250	1080	930
      130	1920	1680	1680	1490	1490	1310	1120	970

      1	Pole class definitions taken from American National Standard specifications and dimensions for wood poles as approved August 7, 1976, under American National Standard Institute, Inc. codified ANSI 05.1-1972.
      2	Piling class definitions as per American Society for Testing and Materials for "round timber piles." As the designation: D 25-58 (reapproved 1964).

      Total Scribner Board Foot VolumeStumpage Value Areas 6 and 7
      	Pole Class1	Piling Class2
      Length	H6	H5	H4	H3	H2	H1	1	2	3	4	5	6	7	9	10	A	B
      20							70	60	50	50	30	30	20	20	20	90	70
      25							80	70	50	50	40	40	30	30	20	100	80
      30							110	90	60	60	50	50	50	40		130	110
      35					190	160	140	100	100	70	60	60	50			140	100
      40				240	240	200	170	120	110	100	70	70				140	100
      45	390	330	330	270	270	220	180	150	110	110	80	70				150	110
      50	460	390	390	340	340	280	240	190	150	150	120					190	150
      55	510	430	430	370	360	300	250	190	150	150						190	150
      60	610	530	530	440	440	380	310	240	200	200						240	200
      65	650	570	570	490	480	410	350	280	220	220						240	200
      70	750	650	650	550	470	470	410	320	260	260						260	210
      75	810	700	700	600	600	500	440	340	270							270	220
      80	960	830	830	710	710	610	510	420	340							220	220
      85	1020	870	870	760	760	640	550	450	360							300	240
      90	1110	970	970	840	840	720	620	500	420							280	280
      95	1160	1010	1010	870	870	740	640	510								360	280
      100	1380	1210	1210	1060	1060	910	780	650								360	280
      105	1430	1250	1250	1100	1100	940	820	690								400	300
      110	1580	1390	1390	1220	1220	1070	920	770								460	340
      115	1660	1470	1470	1280	1280	970	810	680								470	360
      120	1880	1680	1680	1480	1480	1290	1130	950								560	450
      125	1910	1690	1690	1490	1490	1140	970	810
      130	2170	1920	1920	1710	1710	1510	1320	1140

      1	Pole class definitions taken from American National Standard specifications and dimensions for wood poles as approved August 7, 1976, under American National Standard Institute, Inc. codified ANSI 05.1-1972.
      2	Piling class definitions as per American Society for Testing and Materials for "round timber piles." As the designation: D 25-58 (reapproved 1964).

[Statutory Authority: RCW 82.01.060(2) and 84.33.096. WSR 19-02-068, § 458-40-680, filed 12/28/18, effective 1/1/19. Statutory Authority: RCW 82.32.300, 82.01.060(2), 84.33.096, and 84.33.091. WSR 12-14-065, § 458-40-680, filed 6/29/12, effective 7/1/12. Statutory Authority: RCW 82.32.300, 82.01.060(2), and 84.33.096. WSR 06-02-007, § 458-40-680, filed 12/22/05, effective 1/22/06; WSR 05-08-070, § 458-40-680, filed 3/31/05, effective 5/1/05; WSR 03-22-099, § 458-40-680, filed 11/5/03, effective 12/6/03. Statutory Authority: RCW 82.32.300 and 84.33.096. WSR 00-24-068, § 458-40-680, filed 12/1/00, effective 1/1/01. Statutory Authority: RCW 82.32.330, 84.33.096 and 84.33.120. WSR 96-02-056, § 458-40-680, filed 12/29/95, effective 1/29/96. Statutory Authority: RCW 82.32.300 and 84.33.096. WSR 95-14-084, § 458-40-680, filed 6/30/95, effective 7/31/95. Statutory Authority: Chapter 84.33 RCW. WSR 87-02-023 (Order 86-4), § 458-40-680, filed 12/31/86.]