FNR-109
Expanded use of wood fiber for traditional uses, as well as the use of wood as a commercial and domestic energy source are indications that the utilization of logging residues and other small diameter or low value timber will increase. Small diameter timber could be removed during timber stand improvement operations. Logging residues could be harvested along with the rest of the tree and therefore, are likely to be the first material utilized by commercial operations. Logging residues include all of the above ground tree parts, except the stump, left after the sawlogs are removed. Before expanded utilization of small diameter timber and logging residues is realized, some estimate of the weight or volume of available wood is desirable. These estimates could help determine the economic feasibility of removal.
This report will present total tree oven-dry weights for small diameter hard and soft hardwoods, top weight data for sawlog size oak in Indiana, and regional data for oak and other hardwood species. Even on a regional basis, only a limited number of studies have been reported. Therefore, care must be exercised in the application of the data. In all cases, the data were collected on commercially grown forest trees. Open grown trees, or timber with excessively large tops, will give substantially higher yields. Erroneous results can also occur when the data are applied to only one or even small groups of trees.
The top weight data in this publication are given for the oven-dry (105C or 221F) condition. Oven-drying removes all of the water from wood. These oven-dry weights can be converted to weights at different moisture contents. For example, firewood cut to length and split to stovewood size will dry to about 15 to 20 percent moisture content in one full summer under ideal conditions. The following formula is applicable for this conversion:
W = D (1 + M )
-
100
where:
W = weight of wood at any moisture content
D = weight of wood oven-dry (see Tables 2-8)
M = wood moisture content (in percent) for which
"W" is desired
The green moisture content of some common woods is given in Table 1 (Wood Handbook 1974). Therefore, the weight of wood given can also be calculated by using the formula given above. The heartwood moisture content varies from a low of 46 percent for white ash to a high of 114 percent for sycamore; while the sapwood moisture content ranges from a low of 44 percent for white ash to a high of 137 percent for sweetgum. The sapwood moisture content may be lower or higher than the heartwood depending on the species. However, the sapwood will usually dry faster or at least as fast as the heartwood. Heartwood often contains extractives or other obstructions which inhibit drying.
Table 1 also gives the weight per cubic foot of solid wood in the green and air-dried condition. A standard cord containing 128 cubic feet of wood, bark, and air space is assumed to have 80 cubic feet of wood in it. Therefore, the approximate weight of one cord of wood of any particular species can be calculated.
Table 2 presents the total tree oven-dry weights of several small diameter hard and soft hardwood species sampled at different locations. The hard hardwoods include sugar maple, yellow birch, beech, northern red oak, white ash, and red maple from New York (Monteith 1979); sugar maple from the lake states (Steinhill and Winsauer 1976); and hickory, red and white oaks, red maple, and black cherry from the Appalachian Mountains (Wiant 1977). The soft hardwoods include yellow poplar from the Appalachian Mountains (Wartluft 1978; Clark and Schroeder 1977). Even with the large variation in species and sampling location, relatively small differences exist in the total tree oven-dry weights for any of the above hard hardwoods with a Diameter at Breast Height (DBH) of less than about 14 inches. Therefore, the data for each individual species was combined and is shown in Table 2. Being a soft hardwood, yellow poplar is substantially lighter and thus is shown separately.
Tables 3 and 4 give the weight of wood and bark in all branches and the weight of wood and bark for branches equal to or greater than four inches in diameter by tree DBH and merchantable height for 54 red, white and black oak trees from southern Indiana (Dubois County). The trees were felled during November of 1978 and all sawlog size material equal to or greater than about 12 inches (diameter inside bark small end) was removed. During the spring of 1979 branches equal to or greater than four inches in diameter were separated from the smaller material and weighed. Material less than four inches in diameter was also weighed. Ten randomly selected samples from each top were collected to determine current moisture content at time of weighing.
The harvested stand was typical of the timber resource in southern Indiana and much of the central hardwood region. Because of past grazing and cutting practices, tree quality was variable. The stand contained 98 square feet of basal area and 344 trees two inches and larger in DBH per acre. There were 5240 board feet Doyle scale per acre in trees 10 inches and larger. Approximately 80 percent of the stand volume was oak.
Table 5 gives the total top weight by DBH class for white ash, beech, sugar maple, and combined hardwoods sampled from 23 locations in New York state. Sawlogs to a 12 inch top were removed. White ash has a lower top weight than either beech or sugar maple. The top weight for beech trees to a 16 inch DBH was less than that of sugar maple. However, 17 inch DBH or larger beech trees contained more top weight than sugar maple. When the New York data is plotted the curves are much flatter than comparable data for Indiana and the Appalachian Mountains.
Table 6 gives the top weights for all branches and branches equal to or greater than two inches in diameter for yellow poplar from North Carolina. Sawlogs to a 9.5 inch diameter inside bark on the small end were removed. The top weights increased from 366 pounds for a 16 inch DBH tree to 1338 pounds for a 28 inch DBH tree. The weight of branches equal to or greater than two inches in diameter was 81 percent or more of the total top weight and generally increased with an increase in DBH.
Table 7 gives the top weights for all branches and for branches equal to or greater than three inches in diameter for hard and soft hardwoods from West Virginia and Virginia. For a DBH range of 11 to 26 inches, the total weight of the hard hardwoods increased from 514 to 2993 pounds while the soft hardwoods showed only a 308 to 1587 pounds increase. The hard hardwoods were nearly twice as heavy as the soft hardwoods. The percent of top weight for branches greater than three inches in diameter for the hard hardwood increased from 56 to 74 percent over the DBH range of 11 to 26 inches. For soft hardwoods, the increase was from 58 to 79 percent.
Table 8 compares the total top weights for 14, 18, and 22 inch DBH trees for selected species from different geographic locations. In the 22 inch DBH class, oak sampled in all locations always produced more top weight than the other species. For the 18 inch DBH class, oak sampled in Indiana and TVA was heavier than the other species. However, for the 14 inch DBH class large differences do not exist between any of the hard hardwoods. The top weight of the soft hardwoods was always less than that of the hard hardwoods. Variation in top weight of trees of the same species and diameter sampled in different locations could be due to local log utilization standards as well as site variability and stand history.
Top weight is defined as all the above ground material left in a tree after the sawlogs (except for the stump) have been removed. The top weight is greatly affected by the moisture content of the wood. Therefore, all data reported here are on an oven-dry basis. The total top weight of soft hardwoods was always less than the hard hardwoods. Few differences exist n the total top weights of all hard hard- woods in the 14 inch DBH range. In the larger diameter classes, the total top weight of oak was greater than that for the other hard hardwoods. For hard hardwood trees less than 14 inches DBH, little variation exists in total tree oven-dry weights. Small diameter soft hardwoods were lighter than the hard hardwoods.
Moisture Content Weight per Cubic Foot 1/
Species Heartwood Sapwood Green Air-dried2/
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percent pounds
White Ash 46 44 49.8 36.2
Basswood 81 133 41.3 20.6
Beech 55 72 57.3 36.8
Cherry 58 - 46.3 30.6
American Elm 95 92 55.7 40.0
Hackberry 61 65 49.8 31.8
Hickory 71 49 64.3 42.4
Black Locust - 403/ 57.6 43.7
Soft Maple 58 97 48.9 28.7
Sugar Maple 65 72 59.0 36.8
Red Oak 80 69 59.0 35.6
White Oak 64 78 64.0 39.3
Sweetgum 79 137 59.7 30.0
Sycamore 114 130 63.7 30.0
Black Tupelo 87 115 57.7 34.4
Walnut 90 73 57.9 33.7
Yellow-Poplar 83 106 48.7 26.2
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1 Based on one-half heartwood and one-half sapwood
2 Moisture content at 20 percent
3 For mixed heartwood and sapwood
Tree Hard Soft
DBH Hardwoods1/ Hardwoods2/
-----------------------------------------------------
inches oven-dry pounds
4 80 60
6 210 110
8 440 280
10 770 510
12 1180 800
14 1710 1140
16 2190 1520
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1 Includes sugar maple, red maple, beech, yellow birch, red and white
oak. white ash. hickory, and black cherry
2 Includes yellow poplar only
Tree Merchantable Height (feet) DBH 8 12 18 24 30 36 42 48 -------------------------------------------------- inches oven-dry pounds 10 675 630 11 775 723 652 588 12 889 830 749 675 609 13 1021 953 859 775 699 14 1171 1093 986 890 802 15 1344 1255 1132 1021 921 831 16 1543 1441 1299 1172 1057 953 17 1653 1491 1345 1213 1094 18 1898 1712 1544 1392 1256 19 2178 1965 1772 1598 1441 1300 1173 20 2500 2255 2034 1834 1654 1492 1346 21 2869 2588 2334 2105 1899 1713 1545 22 3293 2970 2679 2416 2179 1966 1773 23 3780 3409 3075 2773 2501 2256 2035 24 3913 3529 3183 2871 2590 2336 ---------------------------------------------------- 1 Boxed in areas indicate limits of sample
Tree Merchantable Height (feet) DBH 8 12 18 24 30 36 42 48 ------------------------------------------------------ inches oven-dry pounds 10 425 399 11 493 461 415 375 12 570 531 480 434 392 13 657 614 555 502 453 14 760 710 642 680 524 15 879 821 742 670 606 547 16 1016 949 858 775 700 633 17 1098 992 896 810 732 18 1269 1146 1036 936 846 19 1467 1325 1198 1082 978 883 798 20 1896 1532 1385 1251 1130 1021 923 21 1%1 1772 1601 1446 1307 1181 1867 22 2267 2048 1851 1673 1611 1365 1233 23 2621 2368 2139 1933 1747 1578 1426 24 2737 2473 2235 2019 1825 1649 ----------------------------------------------------- 1 Boxed in areas indicate limits of sample
Species1
Tree White Sugar Combined
DBH Ash Beech Maple Hardwoods
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inches pounds
13 789 832 939 848
14 815 907 987 894
15 843 988 1038 944
16 874 1074 1093 997
17 906 1167 1151 1055
18 940 1266 1214 1116
19 974 1372 1280 1182
20 1014 1483 1350 1250
21 1054 1600 1423 1323
22 1094 1724 1501 1399
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1 Thirty-two trees were sampled for white ash and beech, 33 trees for
sugar maple and 278 for the combined hardwoods. The combined
hardwoods include 15 species native to New York State.
Tree Weight of Weight of Branches Equal to DBH All Branches or Greater Than 2 Inches -------------------------------------------------- inches pounds pounds 16 366 298 18 526 444 20 677 551 22 726 593 24 751 634 26 1436 1270 28 1338 1241 --------------------------------------------------
Hard Soft
Hardwoods1 Hardwoods2
Equal To or Equal To or
Tree Greater Greater
DBH Total Than 3 Inches Total Than 3 Inches
----------------------------------------------------
inches pounds
11 514 287 308 177
12 578 329 344 202
13 650 377 384 230
14 731 432 428 262
15 822 494 477 298
16 925 566 532 239
17 1040 649 594 387
18 1170 743 662 440
19 1316 851 739 502
20 1479 975 824 571
21 1664 1117 919 651
22 1871 1280 1025 741
23 2104 1466 1143 844
24 2367 1679 1275 961
25 2661 1923 1423 1095
26 2993 2203 1587 1247
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1 Based on 31 red oak, 16 chestnut oak, 6 white oak, 2 hickory, 1 ash,
and 1 hard maple
2 Based on 14 yellow poplar, 3 black gum, and 1 cucumber magnolia
DBH (Inches)
Location Species 14 18 22
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Hard Hardwoods
Indiana Oak (white, red, black 980 1555 2273
TVA Oak (black) 804 1360 2071
Virginia and
West Virginia Oak1/ 731 1170 1871
New York Ash 815 940 1094
New York Beech 907 1266 1724
New York Sugar Maple 987 1214 1501
New York Combined 894 1116 1399
hatdwoods2/
Soft Hardwoods
North Carolina Yellow Poplar 289 526 726
Virginia and
West Virginia Mixed soft 428 662 1025
hardwoods3
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1 Based on 31 red oak, 16 chestnut oak, 6 white oak, 2 hickory, 1 ash,
and 1 hard maple.
2 Based on 14 yellow poplar, 3 blackqum, and 2 cucumber magnolia
3 Based on 13 sugar maple, 13 red maple, 32 red oak, 32 beech, 32 white
ash, 31 aspen, 11 yellow birch, 12 hickory, 11 black cherry, 11 American bssswood,
11 white oak, 4 birch, 3 sugar maple, 1 American elm,
and 1 yellow poplar
RR 5/92
Cooperative Extension work in Agriculture and Home Economics, state of Indiana,Purdue University, and U.S. Department of Agriculture cooperating; H. A. Wadsworth, Director, West Lafayette, IN. Issued in furtherance of the acts of May 8 and June 30, 1914. The Cooperative Extension Service of Purdue University is an affirmative action/equal opportunity institution.