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FOREST PRODUCTS LABORATORY. 



izing dimension sizes, by cutting dimension stock directly from the log 

 instead of remanufacturing it from lumber, and by an interchange 

 between industries that would result in the utilization by one industry 

 of what is now regarded as waste in another. Studies along these lines 

 have been undertaken by the Laboratory and will be extended as rapidly 

 as possible. 



SECOND-GROWTH STANDS. 



Another problem of first importance has to do with finding a profitable 

 and economical use for the small sizes and low grades on which we shall 

 have increasingly to depend as the virgin forests are replaced by second- 

 growth stands. This problem includes also the finding of uses for species 

 now without markets. To a considerable extent the practice of forestry 

 is dependent on developing methods by which the material of all species 

 produced by these stands can be used in place of the high-grade material 

 of a few species from virgin forests to which we have hitherto been 

 accustomed. This involves not only perfecting the technique of built-up 

 and laminated construction, but the introduction of new uses and new 

 methods of manufacture. Investigation of these and related problems 

 will go far toward enabling us to eliminate present wastes and to make 

 the most of our wood supply. 



PATHOLOGY. 



The work of this section is conducted by the Bureau of Plant Industry 

 of the Department of Agriculture. General studies of the durability and 

 decay of wood are carried on. 



DURABILITY OF UNTREATED WOOD. 



The relative durability of different woods and the effects of moisture 

 and wood-destroying fungi upon the life of the wood have been studied 

 for many kinds of American woods. Data have been obtained upon the 

 least and most favorable temperatures for the growth of fungi and the 

 amount of heat required to stop their growth. An application of this 

 work is the control of so-called "dry rot" in buildings. 



