Giving you the Edge in Business

Len/Diam	3"	4"	5"	6"	7"	8"	9"	10"	11"	12"	13"	14"	15"	16"	17"	18"
4'	0	0	0	0	1	1	1	1	1	2	2	3	4	4	5	5
5'	0	0	1	1	1	1	1	1	2	2	3	4	4	5	6	7
6'	0	0	1	1	1	1	1	2	2	3	4	4	5	6	7	8
7'	0	0	1	1	1	1	2	2	2	3	4	5	6	7	8	9
8'	0	1	1	1	1	1	2	3	3	4	5	6	7	8	9	11
9'	0	1	1	1	1	1	2	3	3	4	5	6	8	9	10	12
10'	0	1	1	1	1	2	3	3	4	5	6	7	9	10	12	13
11'	0	1	1	1	2	2	3	3	4	5	7	8	10	11	13	15
12'	0	1	1	1	2	2	3	3	4	6	7	9	11	12	14	16
13'	1	1	1	1	2	2	3	4	5	6	8	9	12	13	15	17
14'	1	1	1	1	2	2	3	4	5	7	8	10	12	14	16	19
15'	1	1	1	1	2	2	3	5	6	7	9	11	13	15	17	20
16'	1	1	2	2	3	3	4	6	7	8	10	11	14	16	18	21
17'	1	1	2	2	3	3	4	6	7	8	10	12	15	17	20	23
18'	1	1	2	2	3	3	4	6	8	9	11	13	16	18	21	24
19'	1	1	2	2	3	3	4	6	8	10	12	14	17	19	22	26
20'	1	1	2	2	3	3	4	7	8	10	12	14	18	20	23	27

Len/Diam	19"	20"	21"	22"	23"	24"	25"	26"	27"	28"	29"	30"	31"	32"	33"	34"
4'	6	7	8	8	9	10	11	12	14	15	15	16	18	18	20	20
5'	8	9	10	10	12	13	14	16	17	18	19	21	22	23	24	25
6'	9	11	12	13	14	15	17	19	21	22	23	25	27	28	29	30
7'	10	12	13	15	16	18	20	22	24	25	27	29	31	32	34	35
8'	12	14	15	17	19	21	23	25	27	29	31	33	36	37	39	40
9'	13	16	17	19	21	23	26	28	31	33	35	37	40	41	44	45
10'	15	17	19	21	23	25	29	31	34	36	38	41	44	46	49	50
11'	16	19	21	23	26	28	31	34	38	40	42	45	49	51	54	55
12'	18	21	23	25	28	30	34	37	41	44	46	49	53	55	59	60
13'	19	23	25	27	31	33	37	41	44	47	49	53	58	60	64	65
14'	21	24	27	29	33	35	40	44	48	51	53	57	62	64	69	70
15'	22	26	28	31	35	38	43	47	51	54	57	62	67	69	73	75
16'	24	28	30	33	38	40	46	50	55	58	61	66	71	74	78	80
17'	25	30	32	35	40	43	49	53	58	62	65	70	75	78	83	85
18'	27	31	34	38	42	45	52	56	62	65	68	74	80	83	88	90
19'	28	33	36	40	44	48	54	59	65	69	72	78	84	88	93	95
20'	30	35	38	42	47	50	57	62	68	73	76	82	89	92	98	100

Len/Diam	35"	36"	37"	38"	39"	40"	41"	42"	43"	44"	45"	46"	47"	48"	49"	50"
4'	22	23	26	27	28	30	32	33	35	37	38	39	41	43	45	47
5'	27	29	32	33	35	38	39	42	43	46	47	49	52	54	56	58
6'	33	35	39	40	42	45	48	50	52	56	57	59	62	65	67	70
7'	38	40	45	47	49	53	56	59	61	65	66	69	72	76	79	82
8'	44	46	51	54	56	60	64	67	70	74	76	79	83	86	90	94
9'	49	52	58	60	63	68	72	76	79	83	85	89	93	97	101	105
10'	55	58	64	67	70	75	79	84	87	93	95	99	104	108	112	117
11'	60	63	71	73	77	83	87	92	96	102	104	109	114	119	124	129
12'	66	69	77	80	84	90	95	101	105	111	114	119	124	130	135	140
13'	71	75	84	87	91	98	103	109	113	120	123	129	134	140	146	152
14'	77	81	90	93	98	105	111	117	122	129	133	139	145	151	157	164
15'	82	86	96	100	105	113	119	126	131	139	143	149	155	162	168	175
16'	88	92	103	107	112	120	127	134	140	148	152	159	166	173	180	187
17'	93	98	109	113	119	128	135	143	148	157	161	169	176	184	191	199
18'	98	104	116	120	126	135	143	151	157	166	171	178	186	194	202	211
19'	104	110	122	126	133	142	151	160	166	176	180	188	196	205	214	222
20'	109	115	129	133	140	150	159	168	174	185	190	198	207	216	225	234

Len/Diam	51"	52"	53"	54"	55"	56"	57"	58"	59"	60"	61"	62"	63"	64"	65"
4'	48	50	52	54	56	59	61	63	65	67	70	72	74	77	79
5'	61	63	66	68	71	73	76	79	81	84	87	90	93	96	99
6'	73	76	79	82	85	88	91	95	98	101	105	108	112	116	119
7'	85	89	92	96	99	103	107	110	114	118	123	127	131	135	139
8'	97	101	105	109	113	118	122	126	131	135	140	145	149	154	159
9'	110	114	118	123	127	132	137	142	147	152	158	163	168	174	179
10'	122	127	132	137	142	147	152	158	163	169	175	181	187	193	199
11'	134	139	145	150	156	162	167	174	180	186	193	199	205	213	219
12'	146	152	158	164	170	176	183	189	196	203	210	217	224	232	239
13'	158	165	171	177	184	191	198	205	212	220	228	235	243	251	259
14'	170	177	184	191	198	206	213	221	229	237	245	253	261	270	279
15'	183	190	197	205	212	220	228	237	245	253	263	271	280	290	299
16'	195	202	210	218	227	235	244	252	261	270	280	289	299	309	319
17'	207	215	224	232	241	250	259	268	278	287	298	307	317	329	339
18'	219	228	237	246	255	264	274	284	294	304	315	325	336	348	358
19'	231	240	250	260	269	279	289	300	310	321	332	344	354	368	378
20'	243	253	263	273	283	294	304	315	327	338	350	362	373	387	398

Len/Diam	66"	67"	68"	69"	70"	71"	72"	73"	74"	75"
4'	82	85	87	90	93	96	98	101	104	107
5'	103	106	109	113	116	120	123	127	130	134
6'	123	127	131	135	139	144	148	152	157	161
7'	144	148	153	158	163	167	173	178	183	188
8'	164	170	175	180	186	192	197	203	209	215
9'	185	191	197	203	209	215	222	229	236	242
10'	206	212	219	226	232	240	247	254	261	269
11'	226	233	240	248	256	263	271	280	288	296
12'	247	254	262	271	279	287	296	305	314	323
13'	268	275	284	294	302	311	321	330	340	350
14'	288	297	306	316	325	335	345	356	366	377
15'	309	318	328	339	349	359	370	381	393	404
16'	329	339	350	361	372	383	395	406	418	430
17'	350	360	371	384	395	407	419	432	445	458
18'	370	381	393	406	419	430	444	457	471	484
19'	391	402	415	429	442	454	468	482	497	511
20'	412	423	437	452	465	478	493	508	523	538

Multi-Segment Logs

Multi-segment logs are those logs exceeding the 20-foot maximum single segment length. These logs are divided into two or more segments as nearly the same length as practicable, in accordance with specific rules, and no scaling segment length can ever be longer than 20 feet. Logs with scaling lengths of 21-foot through 40-foot are scaled as two-segment logs. Logs with scaling lengths of 41-foot through 60-foot are scaled as three-segment logs, 61-foot through 80-foot as four-segment logs, etc.

Since lumber is commonly sold in lengths that are multiples of two feet, multiple segment logs are generally divided into lengths that are multiples of two feet. For example, a log measuring 33 feet 0 inches has the allowable trim for a 32-foot scaling length. Logs whose overall scaling length is an even number are called “even length” logs.

When an even length log must be divided into unequal lengths, the shorter segment(s) is always in the small end (top) of the log and the longer segment(s) in the large end. For example, a log measuring 35 feet 2 inches has the allowable maximum trim for a 34-foot scaling length. This log is divided as a 16-foot top segment and an 18-foot bottom segment. A log measuring 45 feet 2 inches is scaled as a 44-foot scaling length. The is divided into three segments: a 14-foot top segment, a 14-foot middle segment, and a 16-foot bottom segment.

Note: In creating the segments, the Butt segment is always assigned the longest length

Logs whose overall scaling length is an odd number are called “odd length” logs. Odd length, multi-segment logs cannot be evenly divided into multiples of two feet. In these instances, one of the segments will be an odd length segment and the other(s) will be even length segments. Again, the overall scaling length is divided into two or more segments as nearly the same length as practicable. For example, a log measuring 31 feet 10 inches is scaled as a 31-foot scaling length. Figure 2-6 shows how it is segmented as a 15-foot top segment and a 16-foot bottom segment.

In all instances when determining segmentation on an odd-length multi-segment log, only one segment will be an odd length segment and the difference between the shortest and longest segment will never be more than two feet.

The Table below shows the Segment breaks for logs up to 120 feet.

Length	# of Segments	Butt Segment	Segment #2	Segment #3	Segment #4	Segment #5	Segment #6
8	1	8
9	1	9
10	1	10
11	1	11
12	1	12
13	1	13
14	1	14
15	1	15
16	1	16
17	1	17
18	1	18
19	1	19
20	1	20
21	2	11	10
22	2	12	10
23	2	12	11
24	2	12	12
25	2	13	12
26	2	14	12
27	2	14	13
28	2	14	14
29	2	15	14
30	2	16	14
31	2	16	15
32	2	16	16
33	2	17	16
34	2	18	16
35	2	18	17
36	2	18	18
37	2	19	18
38	2	20	18
39	2	20	19
40	2	20	20
41	3	14	14	13
42	3	14	14	14
43	3	15	14	14
44	3	16	14	14
45	3	16	15	14
46	3	16	16	14
47	3	16	16	15
48	3	16	16	16
49	3	17	16	16
50	3	18	16	16
51	3	18	17	16
52	3	18	18	16
53	3	18	18	17
54	3	18	18	18
55	3	19	18	18
56	3	20	18	18
57	3	20	19	18
58	3	20	20	18
59	3	20	20	19
60	3	20	20	20
61	4	16	16	15	14
62	4	16	16	16	14
63	4	16	16	16	15
64	4	16	16	16	16
65	4	17	16	16	16
66	4	18	16	16	16
67	4	18	17	16	16
68	4	18	18	16	16
69	4	18	18	17	16
70	4	18	18	18	16
71	4	18	18	18	17
72	4	18	18	18	18
73	4	19	18	18	18
74	4	20	18	18	18
75	4	20	19	18	18
76	4	20	20	18	18
77	4	20	20	19	18
78	4	20	20	20	18
79	4	20	20	20	19
80	4	20	20	20	20
81	5	17	16	16	16	16
82	5	18	16	16	16	16
83	5	18	17	16	16	16
84	5	18	18	16	16	16
85	5	18	18	17	16	16
86	5	18	18	18	16	16
87	5	18	18	18	17	16
88	5	18	18	18	18	16
89	5	18	18	18	18	17
90	5	18	18	18	18	18
91	5	19	18	18	18	18
92	5	20	18	18	18	18
93	5	20	19	18	18	18
94	5	20	20	18	18	18
95	5	20	20	19	18	18
96	5	20	20	20	18	18
97	5	20	20	20	19	18
98	5	20	20	20	20	18
99	5	20	20	20	20	19
100	5	20	20	20	20	20
101	6	18	18	17	16	16	16
102	6	18	18	18	16	16	16
103	6	18	18	18	17	16	16
104	6	18	18	18	18	16	16
105	6	18	18	18	18	17	16
106	6	18	18	18	18	18	16
107	6	18	18	18	18	18	17
108	6	18	18	18	18	18	18
109	6	19	18	18	18	18	18
110	6	20	18	18	18	18	18
111	6	20	19	18	18	18	18
112	6	20	20	18	18	18	18
113	6	20	20	19	18	18	18
114	6	20	20	20	18	18	18
115	6	20	20	20	19	18	18
116	6	20	20	20	20	18	18
117	6	20	20	20	20	19	18
118	6	20	20	20	20	20	18
119	6	20	20	20	20	20	19
120	6	20	20	20	20	20	20

Taper in Long Logs: Distribution of Taper in Second-Cut Long Logs

A second-cut, long log is any log with a scaling length of 21 feet or longer that is not affected by butt swell. The first step is to measure the scaling diameters on both the small end and large end of the log. The difference between these two measurements is the total taper of the log. For example, a log with a scaling length of 32 feet, having a small end diameter of 12 inches and a large end diameter of 16 inches has total taper of 4 inches (16 inches minus 12 inches = 4 inches).

The second step is to divide the total taper by the number of log segments to determine the taper of the top segment. Using our example, a 32-foot scaling length is a 2-segment log (it has two 16-foot scaling length segments). Four inches of total taper divided by 2, equals 2 inches of taper for the top segment. The small end scaling diameter of 12 inches is increased by the 2 inches of taper to arrive at 14 inches for the midpoint, which is the calculated small end diameter of the second segment. When taper can be apportioned in an equal amount to each segment (such as 4 inches of taper in a 2-segment log can be apportioned 2 inches to each segment) it is said to be even taper. When taper cannot be apportioned in an equal amount to each segment (such as 5 inches of taper in a 2-segment log) it is said to be uneven taper. As noted earlier, trees grow with increased taper in the top end. Uneven taper is handled by applying the excess taper to the top log segment(s). For example, a log with a scaling length of 32 feet having a small end diameter of 12 inches and a large end diameter of 17 inches has total taper of 5 inches (17 inches minus 12 inches = 5 inches). Applying the excess taper to the top segment results in 3 inches of taper for the top segment and 2 inches of taper for the bottom segment. The midpoint, small end diameter of the bottom segment is 15 inches, determined by taking the top diameter of 12 inches and adding 3 inches of taper.

Distribution of Taper in Butt-Cut Long Logs

There is normally a noticeable “flare” or swell on butt logs at the point of severance from the stump, and a greater rate of taper may be present for several feet above this point. Therefore, for taper distribution, multi-segment butt-cut logs are not measured on the large end to calculate a small end diameter for the butt segment. Instead, the small end diameter of the butt segment is determined by either actual measure or the use of “standard” taper. Standard taper is an average taper that is uniformly applied to butt-cut, long logs. It is developed from actual measure studies, based upon species, log lengths, and localities of origin (different geographic areas). In Idaho, all gross scale determination of butt-cut, long logs must be determined in accordance with criteria set forth in the table shown below. Various standard tapers will apply to the gross scale determination of butt-cut, long logs that are scaled in most areas of Idaho. However, in the absence of a standard taper listing for butt-cut, long logs from a particular locale, actual taper (caliper measure) will apply. The standard tapers listed in the table below are based on averages developed from caliper measurements. Any particular log may, or may not, have the actual taper predicted by the taper table. It is important to remember that regardless of the actual, physical midpoint diameter(s) of any particular log, that midpoint diameter(s) will be treated as if it is the size predicted by the taper table. For example, a Ponderosa Pine butt-cut log with a 32-foot scaling length. The small end diameter is measured as 16 inches. Standard taper assigns a midpoint diameter of 18 inches, even though the actual, physical measurement is 17 inches. Another example is a Ponderosa Pine that has a small end diameter of 16 inches, but an actual physical size at midpoint of 19 inches. Again, standard taper requires that the midpoint will be treated as if it measures 18 inches for gross scale computation purposes. A log scaler must always visualize the scaling cylinder as conforming to the actual, physical size of the log at midpoint(s) regardless of the “inch-size” assigned by the standard taper rules.

MIDPOINT TAPER ON MULTI-SEGMENT BUTT LOGS
Region 1 - North Idaho Area (North of the Salmon River, including all of Idaho county except that portion which is both south of the main Salmon river and east of the Little Salmon River. Also includes western Montana, and the northeastern Washington area bounded by the Snake River on the south, to the Columbia River, north to the Okanogan River, north to Canada) --- Midpoint taper(s) shall be a standard taper as follows:
Larch & Lodgepole Pine	21’-48’	Shall be 1-inch per segment.
Larch & Lodgepole Pine	49’-60’	Shall be 2-inch top segment, 1-inch remaining segment.
Cedar	21’-40’	Shall be 2-inches per segment.
All Other Species	21’-40’	Allow 1-inch taper on pieces with an odd top diameter; allow 2-inch taper on pieces with an even top diameter (Odd-Even Rule).
All Species (except Larch & Lodgepole Pine)	41’-60’	Take two measurements, small end and 16’ up from the butt. The diameter at the 16’ measurement point shall be determined by actual measure. Apply calculated taper distribution to determine scaling diameter of the second segment.
All Species	61’ and longer	Take two measurements, small end and top of the second segment up from the butt. The top diameter of the second segment shall be determined by actual measure. Apply calculated taper distribution to top segment(s) and standard taper rule for the appropriate species to bottom segment.
Region 2 - East-Central Idaho Area (Includes these counties: Lemhi, Custer, Butte, Bingham, Power, Oneida, Franklin, Bear Lake, Bannock, Caribou, and that portion of Bonneville lying south of the Snake river) --- All midpoint taper(s) shall be determined on the basis of actual taper.
Region 3 - Eastern Idaho Area (All counties lying to the east and north of Region 2, and including all of the Targhee National Forest) --- Midpoint taper(s) shall be a standard or actual taper as follows:
Douglas Fir & Alpine Fir & Engelmann Spruce	21’-40’	Shall be 2-inch standard taper.
Lodgepole Pine	21’-30’	Shall be 1-inch standard taper.
Lodgepole Pine	31’-40’	Shall be 2-inch standard taper.
Any Species	21’-40’	Shall be actual taper.
Region 4 - Southwest Idaho Area (South of the Salmon River, including that portion of Idaho county which is both south of the main Salmon river and east of the Little Salmon River. Includes all counties lying to the west of Region 2) --- Midpoint taper(s) shall be a standard or actual taper as follows:
Larch	21’-40’	Shall be 1-inch standard taper.
All Other Species	21’-40’	Shall be 2-inch standard taper.
All Species	41’ and longer	Shall be actual taper.
Region 5 – Nevada-Utah-Wyoming Area (Adjoining states to the south or east of southern Idaho) --- All midpoint taper(s) shall be determined on the basis of actual taper.
Region 6 – Southeast Washington & East Oregon Area (South of the Snake River and east of the foothills in the Cascade mountain range) --- Midpoint taper(s) shall be a standard or actual taper as follows:
Larch	21’-40’	Shall be 1-inch standard taper.
All Other Species	21’-30’	Shall be 1-inch standard taper.
All Other Species	31’-30’	Shall be 2-inch standard taper.
All Species	41’ and longer	Shall be actual taper.
Region 7 – All Other Areas (Includes logs produced from timber growing in any area other than Regions 1 through 6) --- All midpoint taper(s) shall be determined on the basis of actual taper.