734 



Yearbook^ of Agriculture 1949 



depends on the location of the mine. 

 In the precious-metal mines all in 

 the West western pines and Douglas- 

 fir were favored, while in the anthra- 

 cite mines of Pennsylvania, oak was 

 way ahead and pine a poor second. 



In 1935, about half of all mine tim- 

 ber was sawed, whereas 30 years earlier 

 two-thirds was round, split, or hewed. 

 But, unlike poles or railroad ties, the 

 preservative treatment of mine timbers 

 has showed little change. As late as 

 1935, only 1 percent, in volume, of 

 mine timber was treated; also, only 14 

 percent of all mine material was steel 

 and concrete. Evidently the fact that 

 mine timbers in most cases are aban- 

 doned after a short time makes it un- 

 profitable to resort to preservative 

 treatment or to use the more costly 

 materials. 



As of 1935, it was estimated that re- 

 quirements in the next 10 years would 

 rise to something like 250 million cubic 

 feet, of which some 1 30 million would 

 be in the round and the rest, equiva- 

 lent to 550 million board feet, sawed 

 timber. 



In 1950-55, for all mines and 

 quarries in the United States, it is 

 estimated that potential annual re- 

 quirements for round, split, and hewed 

 timber will approximate 220 million 

 cubic feet, with little change 50 years 

 hence. 



Under good forest-management 

 practices such quantities can be got 

 without heavy drain on saw-timber 

 growing stocks. Mine timbers can be 

 cut chiefly from the smaller or poorer 

 trees removed in improvement cuttings 

 in stands being managed primarily for 

 higher-quality products. 



RAILROAD TIES are mostly sawed, 

 and because sawed material is classed 

 as lumber, the requirements for rail- 

 road cross ties will be discussed later, 

 under lumber requirements of the 

 railroads. The latest record of tie con- 

 sumption, based on the number of ties 

 preservatively treated in 1947, showed 

 63 percent of all cross ties sawed and 

 37 percent hand-hewed, out of a total 



of nearly 48 million. Because at least 

 90 percent of all cross ties are treated, 

 somewhat more than 50 million ties 

 may be taken as the current annual 

 consumption. 



It is estimated that the potential 

 annual requirement for all railroad 

 cross ties in 1950-55 is about 52 mil- 

 lion, of which about 22 million will be 

 hewed equivalent to 238 million 

 cubic feet. Requirements for hewed 

 ties 50 years hence are estimated to be 

 substantially lower, in line with the 

 generally increasing proportion of 

 sawed timber products as compared 

 with hewed perhaps not more than 

 18 million, or 194 million cubic feet. 



THE HEAVIEST DRAIN on the forest 

 is caused by cutting sawlogs to make 

 lumber. Although the per capita con- 

 sumption of lumber has declined from 

 a peak of more than 500 board feet 

 in the early 1900's to less than 300 feet 

 at present, the growth in population 

 compensates in a large measure for de- 

 clining per capita use. Lumber produc- 

 tion in 1947 and 1948 (about 35.5 

 billion board feet) was only 5 percent 

 below the average for the decade from 

 1920 to 1930. 



Based on estimated potential lum- 

 ber requirements in 1950-55, the major 

 fields of lumber use rank in importance 

 as follows (in billion board feet and 

 percentages) : 



Construction (including 



railroad car lumber, Billion 



flooring, and mill- board feet Percent 



work) 31.5 74 



Fabricated wood prod- 

 ucts 5.0 12 



Shipping uses 6. 14 



Total. 



42.5 



100 



Lumber is used in an endless num- 

 ber of structures houses, barns, fac- 

 tories, business buildings, mining struc- 

 tures, waterfront facilities, airports, 

 fire towers, barracks. Of greatest im- 

 portance now is housing. 



HOUSING (other than farm houses) 

 represents nearly 35 percent of total 

 construction requirements; farm con- 



