104 



TECHNICAL QUALITIES OF THE TREES 



Specific 

 gravity 



over 0"75 



IV. Odor. Odor is important for the use of wood in the pacl<age industry. The strong odor of fresh 

 wood is usually lost in the course of seasoning. The following species retain, however, a characteristic 

 odor: — Sweet birch, sassafras, red cedar, white cedar. 



(D) INNER QUALITIES, or qualities discernible by mechanical tests. 

 I. Specific gravity: - 



(a) Pure wood fibre forms in fresh wood, with broad leafed species of temperate climates, about 

 35 per cent of the entire weight, while conifers show an average of about 25 per cent; 



(b) Air-dried wood still retains from 10 per cent to 15 per cent of water. If the dry kiln reduces 

 the percentage of water below that figure, the hygroscopicity of the wood will speedily cause 

 it to return; if it is much reduced, wood looses or changes its fitness for technical use; 



(c) Factors influencing specific gravity of air-dried wood within the same species are: — 



1. The width of the rings, in ring-porous hardwoods and in conifers forming heartwood. 



2. The incrustation of rosin, tannin, and pigments in the heart. 



3. The age of the tree. 



4. The decay of the fibre. 



5. The section of the tree, since roots are very light, butt logs heavy, bole fairly light, and 

 branches fairly heavy. 



In the case of the diffuse-porous hardwoods and of conifers without heart, no rule can 

 be given relative to specific gravity of inner and outer layers, of wide and narrow rings. 



(d) Air-dried lumber has, on an average, the following weights :- 



Species 



Turkey oak, hickory, service-bush 



Ash, white and red oak, locust, beech, hornbeam, hard 



maple, pear tree 



Elm, soft maple, apple tree, sycamore, birch 



Horse chestnut, chestnut, yellow poplar, larch, longleaf pine 

 Yellow pine, Douglas fir, spruce, fir, willow, cottonwood 

 White and sugar pine ... 



(e) Rules. 



1. Specific gravity times 5,200 equals the weight of 1,000 feet b. m. of sawn lumber, since 

 1,000 superficial feet of water 1 inch deep weigh 5,200 lbs. 



2. Specific gravity times 8,000 times "cordwood reducing factor" equals the weight of a cord 

 of wood, since 128 cubic feet of water weigh 8,000 lbs. 



(f) Heavy planks do not dry so thoroughly as thin boards. 'U oak requires four months, and 



'/i opiar requires three months to become "shipping dry;" 



(g) Weight determines freight and custom charges; also adaptability to packages, floatability in flumes 

 and rafts, and possibility of loose driving. 



For rates of freight, compare Schenck's Forest Policy, pages 31 to 33. 

 Transcontinental freight rates on lumber are (Eastbound) close to 50 cents per 100 lbs. 

 Transatlantic freight rates are close to 16 cents per 100 lbs. 

 Freight rates from Asheville, N. C, are:- 



To New York, lighterage free 



To Philadelphia 



To Baltimore 



To Chicago 



To Cincinnati 



The freight rate on logs for 50 miles is at least <^5 per car load; for 100 miles at least ^6. 



070- 

 0-60- 

 0.55- 

 0-45 ■ 



0-75 



0-70 



060 



■0-55 



under 0"45 



Weight of 

 1,000 feet b. m. 



over 4,000 lbs. 



about 3,750 lbs. 

 about 3,400 lbs. 

 about 3,000 lbs. 

 about 2,600 lbs. 

 about 2,200 lbs. 



