THE TRAINING OF A FORESTER 



growth and life which distinguish the trees 

 which are important in forestry. 



Forest Physiography: 



Trees grow in the soil. It is important to 

 know something of the origin of soils and 

 their properties and values, and of the 

 principal soil types, with special reference 

 to their effect upon plant distribution and 

 welfare. The origin, nature, value, and con- 

 servation of humus, that most essential in- 

 gredient of the forest floor; the field methods 

 of mapping soil types; the rock types most 

 important in their relation to soils, how they 

 are made up, how they make soil, and where 

 they occur — something should be learned of 

 all this. Finally, under this head, the stu- 

 dent ought to get a usable knowledge of the 

 physiographic regions of the United States, 

 their boundaries, geologic structure, topog- 

 raphy, drainage, and soils, — all this natu- 



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