THE WOOD OF THE WHITE PINE. 



By FILIBERT ROTH, Division of Forestry. 



White Pine is a favorite material with the wood consumer in the Northeastern States on 

 account of the combination of qualities it possesses. It is a light, soft, uniform, straight-grained 

 timber, to be had iu all markets in any quantity and in all dimensions, from the ship's mast to the 

 clapboard. It seasons well, shrinks and warps but little, is quite durable, insect-proof, and takes 

 oil and paint and has a good color, is light to handle, easy to saw and plane, takes nails without 

 splitting, and is, in short, the ideal material for the carpenter and joiner, who handles the bulk 

 of the 30 to 40 billion feet of sawed timber and lumber annually used in this country, of which 

 White Pine furnishes over 30 per cent. 



CHARACTER AND PHYSICAL PROPERTIES OF THE WOOD. 



The structure of White Pine, like that of other pines, is simple. Ninety per cent and more 

 of the weight of the dry wood is formed by the common wood fibers, or tracheids, 0.12 to 0.20 

 inches long, well suited for pulp material./The spring wood of each annual ring passes gradually 

 into the summer wood and thus the sharply defined bands of hard, dark and soft, light-colored 

 material so conspicuous in the rings of all hard pine, especially Longleaf and Cuban Pine, are 

 absent in White Pine, making the cutting of the wood by either plane or saw much easier 

 than is the case with hard pin esyoap wood and heartwood are quite distinct the former white, 

 the latter with a slightly brownish cast-^The change from sapwood to heartwood takes place earlier 

 in the young tree and the younger portions of old trees than in older timber. Thus, in a thrifty 

 sapling thirty years old the sapwood shows about eighteen rings on the stump, but only ten rings 

 35 feet from the ground. In trees over one hundred years old the number of rings in the sapwood 

 is generally over thirty at the stump, decreasing often to fifteen or twenty near the top. The 

 number of rings in the sap, as in other pines, is smaller in thrifty and greater in slow-growing 

 trees, while the width of the sapwood is generally least in slow-growing timber. Compared to 

 other pines, White Pine has a narrow sap at all periods of its growth. While in the hard pines, 

 like the Longleaf Pine, and still more in Loblolly and Shortleaf Pines, the sap forms generally 

 from 50 to 75 per cent of the log, it is generally less than 35 per cent of mill-sized timber in White 

 Pine. This highly valuable property of the White Pine is found in all localities, even in Europe, 

 where the tree has been widely planted. 



SPECIFIC WEIGHT. 



To determine specific the weight of the wood and other physical properties a collection of 

 seventy-three trees was made, including material from the New England States, Michigan, and 

 Wisconsin, and also from the mountains of North Carolina. 



The specific weight of the greenwood varies chiefly with the amount of sapwood and conse- 

 quent abundance of moisture, since the heartwood contains but little water outside of its cell 

 walls (except in some cases where the heartwood near the stump also contains liquid water). 

 Generally the weight of the greenwood varies from about 40 to 50 pounds per cubic foot, and is 

 greater in young poles than in old timber, which latter on this account floats readily, rarely sink- 

 ing, even after years of immersion. 



The specific weight of the kiln-dry wood varies, generally from 0.33 to 0.40 (20 to 25 pounds 

 per cubic foot), is greater in the old tree than iu the young sapling, is greater at the stump than 



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