UNIVERSITY OF CALIFORNIA PUBLICATIONS COLLEGE OF AGRICULTURE AGRICULTURAL EXPERIMENT STATION BERKELEY, CALIFORNIA A WHITE FIR VOLUME TABLE BY DONALD BRUCE BULLETIN No. 329 August, 1921. UNIVERSITY OF CALIFORNIA PRESS BERKELEY, CALIFORNIA David P. Barrows, President of the University. EXPEKIMENT STATION STAFF HEADS OF DIVISIONS Thomas Forsyth Hunt, Dean. Edward J. Wickson, Horticulture (Emeritus). , Director of Resident Instruction. C. M. Haring, Veterinary Science, Director of Agricultural Experiment Station. B. H. Crocheron, Director of Agricultural Extension. Hubert E. Van Norman, Vice-Director; Dairy Management. James T. Barrett, Acting Director of Citrus Experiment Station; Plant Pathology. William A. Setchell, Botany. Myer E. Jaffa, Nutrition. Ralph E. Smith, Plant Pathology. John W. Gilmore, Agronomy. Charles F. Shaw, Soil Technology. John W. Gregg, Landscape Gardening and Floriculture. Frederic T. Bioletti, Viticulture and Fruit Products. Warren T. Clarke, Agricultural Extension. John S. Burd, Agricultural Chemistry. Charles B. Lipman, Soil Chemistry and Bacteriology. Ernest B. Babcock, Genetics. Gordon H. True, Animal Husbandry. Walter Mulford, Forestry. Fritz W. Woll, Animal Nutrition. W. P. Kelley, Agricultural Chemistry. H. J. Quayle, Entomology. Elwood Mead, Rural Institutions. H. S. Reed, Plant Physiology. L. D. Batchelor, Orchard Management. J. C. Whitten, Pomology, f Frank Adams, Irrigation Investigations. C. L. Roadhouse, Dairy Industry. F. L. Griffin, Agricultural Education. John E. Dougherty, Poultry Husbandry. W. B. Herms, Entomology and Parasitology. L. J. Fletcher, Agricultural Engineering. Edwin C. Voorhies, Assistant to the Dean. Division of Forestry Walter Mulfokd Woodbridge Metcalf Donald Bruce Emanuel Fritz t In cooperation with office of Public Roads and Rural Engineering, U. S. Department of Agriculture. A WHITE FIR VOLUME TABLE By DONALD BRUCE White Fir (Abies concolor) is of increasing commercial importance. A few years ago this tree was usually left standing during logging operations, as the value of lumber to be secured therefrom was not sufficient to repay the cost of manufacture. To-day it is usually logged, and at a profit, and in the future, as timber becomes scarcer, its value will increase still more. It is therefore both natural that no accurate volume table for this species should have previously been prepared, and important that one should be made available for future use. By means of the three-part table herein presented, the average volume in board feet of trees of given diameters and heights may be accurately determined. The table will not, however, give more than approximately the volume of an individual tree. As every woodsman knows, trees of the same diameter and height may vary widely in volume. Some trees will therefore be larger than the tabular values indicate and others smaller, but in averages of many trees these dis- crepancies tend to counteract each other and for large groups of trees disappear. It is worth while to emphasize this point. Many woodsmen have noted that an ocular estimate of an individual tree may be more exact than one made by means of a volume table, and have hence thought such tables useless. It must be remembered, however, that the exact volumes of single trees are rarely of use, for what the timber owner or operator is interested in is the combined or total volume of all the trees of a given species on some specified area. Volume tables based on the averages of hundreds of accurately measured trees, will give this result as exactly as it is possible to obtain it, for they reduce to a minimum the factor of the personal judgment of the estimator. This is true, however, only where the table is properly used, and the follow- ing precautions must be observed. The right table must be selected. It has been found impossible to prepare a single table that would be accurate for the whole state of California, since growing conditions differ widely, and differences in the form or shape of trees of similar height and diameter result. It has been established, however, that this form is essentially similar on two tracts, even if quite remote from one another, if the maximum 42 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION average height to which the trees grow at maturity is approximately the same. To determine the "site" of any given tract, then, the aver- age height of the tallest tenth of the merchantable trees should be estimated. If this be over 93^ 16-foot logs, Table I should be used; if 73^2 or under, Table III, and for intermediate values, Table II. Heights should be measured (or estimated if the estimator has sufficient skill) in 16-foot logs, to the point in the top where the tree is 8 inches in diameter inside the bark. If, in accordance with the logging practice of any region, it is evident that this represents too close a utilization, a deduction for unused tops should be made in connection with the cull factor. Diameters should be measured (or estimated) outside the bark at 43^ feet from the ground, measuring (in the case of sidehill timber) from the average ground level. A deduction should be made for cull. The table is based on trees measured as if sound, unbroken, and to be completely utilized. Per- centage reductions must therefore be made for (a) Rot, if present. (b) Breakage, if inevitable even with careful handling. (c) Unused tops (see above). (d) Unused stumps (if the logging practice of the region cuts stumps materially higher than 18 inches). This cull percentage for white fir commonly ranges from 15 to 35 per cent, including all the above items; of these only the first two, however, are of much importance. Bulletin 329 A WHITE FIR VOLUME TABLE 43 TABLE I. Site I (Tallest 10% Merchantable Trees of Stand 9.6 Logs or Over) Height — Number of 16-Ft. Logs Diameter Breast- High Inches 10 '... 12 1 2 3 4 5 6 7 8 9 10 11 12 3 4 4 4 5 5 7 8 10 11 9 11 13 16 19 VOLU 12 15 19 23 28 ME 30 37 Boar 48 D FE ET IN Tens 14 16 18 20 13 15 17 19 23 28 32 38 44 34 42 49 58 67 45 56 66 78 90 57 70 82 97 113 68 83 98 117 136 97 114 136 159 156 182 22 24 26 28 30 49 56 63 69 75 85 95 106 117 101 114 128 142 157 128 144 161 179 198 154 174 194 216 238 181 204 227 253 279 207 233 260 290 320 234 263 294 327 360 292 327 364 401 32 34 36... 38 441 40 128 139 151 172 188 204 221 239 217 237 258 279 301 262 286 311 336 364 307 335 364 394 426 352 384 418 452 489 397 432 471 509 551 442 481 524 567 613 487 42 528 44 577 46 625 48 676 50 257 324 347 367 391 418 443 469 458 489 520 549 525 561 596 630 666 592 632 672 710 751 659 703 748 791 836 726 52 774 54 824 56 871 58 921 60 702 794 885 936 Stump height 1.5 feet. Trees scaled in 16-foot logs with 0.3 foot trimming allowance, to 8 inches diameter inside bark in top, by Scribner Decimal C. rule * Basis, 841 tree measurements taken by U. S. Forest Service, and 27 by U. S. Bureau of Plant Pathology on the Stanislaus National Forest and in the Yosemite National Park. Table prepared from taper curves by frustum form factor method. Aggregate check against basic trees shows error of -0.24%. ♦This rule has been adopted as standard by the TJ. S. Forest Service. Its values multiplied by 10 are essentially the same as those of the Spaulding rule, which is the legal rule for California. 44 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION TABLE II. Site II (Tallest 10% Merchantable Trees of Stand from 7.6 to 9.5 Logs.) Height — Number of 16-Ft. Logs Diameter Breast- High Inches 1 2 3 4 5 6 7 8 9 10 11 12 VOLU ME Boar D FE ET IN Tens 10 4 6 12 15 12 5 8 13 18 14 5 9 15 22 16 5 11 18 25 33 18 5 12 20 30 39 20 13 15 23 28 35 42 46 55 58 69 22 24 16 31 48 64 80 96 112 128 26 18 36 55 75 93 112 130 148 28 42 63 85 107 128 150 172 30 46 70 94 120 144 169 194 32 52 58 79 88 106 118 131 134 148 165 162 179 197 189 209 234 216 239 266 269 298 34 36 38 144 181 218 256 293 330 40 158 199 240 281 323 365 42 218 237 263 286 308 335 353 385 397 433 482 44 46 310 338 364 396 418 454 470 512 524 569 48 50. 366 394 428 461 493 526 561 491 528 566 603 644 554 595 638 679 726 616 662 710 756 808 52.... 54... 56... 58.... 60 599 687 775 864 Stump height 1.5 feet. Trees scaled in 16-foot logs with 0.3 foot trimming allowance, to 8 inches diameter inside bark in top, by Scribner Decimal C. rule. Basis: 124 tree measurements taken by U. S. Forest Service on the Plumas and Tahoe National Forests, and 179 by the U. S. Bureau of Plant Pathology on the Sierra National Forest. Table prepared from taper curves by frustum form factor method. Aggregate check against basic trees shows error of -0.42%. Bulletin 329 A WHITE FIR VOLUME TABLE 45 TABLE III. Site III (Tallest 10% of Merchantable Trees of Stand 7.5 Logs or Under) Height — Number of 16-Ft. Logs Diameter Breast- High Inches 10 12 14 16 18 1 2 3 4 5 6 7 8 9 10 11 12 4 5 5 5 5 7 9 10 11 11 13 15 16 18 20 23 26 29 VOLU 34 38 ME 48 Boar D FE ET IN Tens 20 22 12 14 15 17 22 26 28 33 38 32 38 44 52 58 43 52 60 69 78 55 65 74 85 98 103 118 24 26 28 30 41 47 53 57 64 72 80 89 97 86 96 107 118 129 109 121 135 148 165 131 146 163 179 197 155 172 190 211 232 177 197 217 241 266 32 34 36 38 40 105 142 156 169 183 199 179 196 213 231 250 217 236 258 279 302 254 277 301 326 354 291 318 346 375 406 42 44 46 48 50 52 270 291 310 329 351 325 349 374 397 424 382 410 438 466 498 437 471 502 534 571 492 530 567 602 642 54 56 58 60 372 448 526 604 683 Stump height 1.5 feet. Trees scaled in 16-ft. logs with 0.3 foot trimming allowance, to 8 inches diameter inside bark in top, by Scribner Decimal C. rule. Basis: 206 tree measurements taken by U. S. Bureau of Plant Pathology in the Tahoe and Siskiyou regions. Table prepared from taper curves by frustum form factor method. Aggregate check against basic trees shows error of -0.17%.