OUR COMMON WOODS 233 



Wood light, soft, not strong, straight-grained, fairly easy 

 to work. Cottonwood can be separated from other light 

 and soft woods by the fineness of its rays, which is equaled 

 only by willow, which it rather closely resembles. 

 The wood is largely used for boxes, general construction, 

 lumber, and pulp. 



How to judge the quality of wood: To know the name 

 of a piece of wood means, in a general way, to know certain 

 qualities that are common to all other pieces of wood of that 

 species, but it does not explain the special peculiarities of 

 the piece in question or why that particular piece is more 

 suitable or unsuitable for a particular purpose than another 

 piece of the same species. The mere identification of the 

 wood does not explain why a particular piece is tougher, 

 stronger or of darker color than another piece of the same 

 species or even of the same tree. The reason for these 

 special differences lies in the fact that wood is not a homo- 

 geneous material like metal. Within the same tree different 

 parts vary in quality. The heartwood is generally heavier 

 and of deeper color than the sapwood. The butt is superior 

 to the top wood, and the manner in which the wood was 

 sawed and dried will affect its quality. Knots, splits, 

 checks, and discoloration due to incipient decay are defects 

 worth considering. Wood that looks lusterless is usually 

 defective, because the lack of luster is generally due to 

 disease. Woods that are hard wear best. Hardness can 

 be determined readity by striking the wood with a hammer 

 and noting the sound produced. A clear, ringing sound 

 is a sign of hardness. The strength of a piece of wood 

 can be judged by its weight after it is well dried. Heavy 

 woods are usually strong. A large amount of late wood 

 is an indication of strength and the production of a clear 

 sound when struck with a hammer is also an evidence of 

 strength. 



