CHAPTER XIX 

 THE DIFFERENT PROPERTIES OF WOODS 



As we have already learned, wood is not simple in its 

 structure, but is made up of many very small cells. The 

 cells differ in different woods and even in the same wood 

 there may be several kinds of cells each serving a different 

 purpose. The different kinds and arrangements of cells give 

 rise to the different properties in woods. The reason why one 

 wood is soft and another hard, or why one wood is strong 

 and another weak is because each has a different structure. 

 Often in the same kind of tree the wood will vary in its prop- 

 erties when grown in different situations and when grown at 

 different rates. Even in the same tree the properties of the 

 wood will vary in different parts of the stem. The heartwood 

 will have different properties from the sapwood and the 

 wood of the butt log from the wood of the top logs, the wood 

 from the quickly grown sapling of the abandoned field from 

 that of the slowly grown forest tree. Even the manner in 

 which the wood was sawed from the log and the method of 

 drying and seasoning will influence the behavior and quality 

 of the wood. However, these differences in the same kind of 

 wood are not very pronounced. 



In the selection of a wood for a particular purpose its prop- 

 erties must be known. Woods often bring a high price because 

 of their adaptability for some special use and for which no 

 other wood will serve the purpose as well. There are no 

 trees that produce worthless wood. Even some of the so-called 

 weed trees in the woodlot, such as dogwood and ironwood, 

 have special uses for which they are of value. 



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