200 



AMERICAN FORESTRY 



Yellow birch and sweet birch, with beech, furnish 'JO 

 per cent of all the hardwood used in destructive dis- 

 tillation in the United States. Mill waste and cordwood 

 from material that remains in the woods after logging 

 are carried to large plants, where the wood is heated 

 to a high temperature in retorts. Wood alcohol and 

 acetic acid are driven oft in gaseous form by the heat, 

 and the vapors are then condensed and purified. The 



BIRCH KIJADY I-OR THli MILL 



Log pond of a large Wisconsin sawmill containing several million feet of hardwood logs ready 

 to be manufactured into lumber and other timber products. A large majority of these 

 logs are birch. 



charcoal which remains in the retorts is used as fuel 

 for the home, bakeries and shops ; in blast furnaces ; in 

 the manufacture of gunpowder, and for filtration in 

 sugar refineries. The wood alcohol is used for fuel, but 

 principally as a solvent in making varnishes and shellacs, 

 and in the manufacture of dyes, artificial leather and 

 other commodities. The acetic acid is recovered as 

 acetate of lime and is then refined to make ether, ace- 

 tone, acetic acid and wood vinegar. Acetone is a neces- 

 sity in the manufacture of smokeless powder. 



The wood of sweet and yellow Ijirch is so hard and 

 strong, resisting the cutting of the rails, that it is now in 

 demand for railroad ties. Since the wood in its natural 

 state will decay in three or four years after it is placed 

 in the ground, the ties are creosoted before they are put 

 in the track. At the creosoting plant, after the bark is 

 removed, the ties are loaded on trucks and run into long 

 steel cylinders. The ends of the cylinders are tightl\- 

 closed and creosote oil is pumped into them and forced 

 into the ties under pressure. The creosote penetrates 

 deep into the wood and prevents fungi from attacking and 

 rotting it. The life of tlic tie is thus increased to 12 

 or 16 years, or more. 



Paper birch is at present commercially most impor- 

 tant in New England, but Minnesota has a large supply 

 that offers excellent opportunity for development. This 

 wood is of medium weight and hardness, strong, tough, 

 close grained and of uniform texture. Green wood is 



heavy and hard to handle on account of the sap, but when 

 dry it becomes fairly light in weight. The wood rots 

 very quickly in contact with the ground. The bark is 

 durable, because the oil it contains keeps out moisture 

 and prevents rapid decay. The appearance of the bark 

 often gives a clue to the quality of the vrood. Trees 

 with dark-colored, close bark are apt to have tough, 

 stringy wood, while those with chalky-white, papery 

 bark generally have smooth, easily 

 worked wood. Its even grain and 

 smooth, clean surface when worked, its 

 ability to hold its shape after seasoning, 

 combined with the ease with which it 

 can be shaped on the lathe, makes paper 

 birch especially valuable for the manu- 

 facture of spools, shoe pegs, shoe shanks 

 (used in moulding the instep of certain 

 styles of shoes), dowels, toothpicks and 

 many wooden novelties where a nice fin- 

 ish is required. IMore than half the cut 

 of paper birch in New England, exceed- 

 ing 40,00 cords per year, is manufac- 

 tured into spools. About 3,000 cords are 

 used in New England each year in the 

 manufacture of toothpicks, furnishing 

 more than half the total output. Wood 

 for this use is specially selected and is 

 worth $20 to $25 per cord. Wooden 

 boxes for tacks, face powder and 

 salves, one-piece trays, curtain rings. 



Photojrat'h from American Lnuibcrma)!. 



A TYPICAL PIECE OF BIRCH TIMBER 



A yellow birch butt log lying in the forest ready for removal to the 

 ' sawmill. This is typical of the timber which the forests of Wis- 

 consin produce. 



clothes pins, pail handles and hundreds of similar articles 

 are very largely made of paper birch. 



The wood is too soft for hardwood lumber and not 

 sufficiently striking in appearance to be popular for fur- 

 niture or interior finish. It is too perishable for use in 

 the open without preser\-ative treatment. It is adapted 



