34 FORESTS AND MANKIND 



only in the best localities they are the aristocrats of the forest 

 world. They need deep, well-watered, fertile soil and direct 

 sunlight. Others less ambitious, more philosophic, are able to 

 get along with very little of nature's favor. We find them out 

 in the arid places and on steep hillsides or even clinging to the 

 barren rock. And some others that have been unable to grow 

 tall and reach the sunlight, like their more hardy companions 

 have learned to get along without. The dogwood or the beech, 

 for example, we find them quite thrifty and apparently con- 

 tented doing well with the few patches of light that fall from 

 between the crowns of their more lofty companions. 



These we call tolerant trees for they are able to tolerate deep 

 shade. They form the understory of the forest while above 

 them tower the taller trees that are intolerant of shade and that 

 form the dominant trees of the forest. 



The presence of species of varying tolerance makes the forest 

 a many-storied structure rising from the low tolerant species, 

 up through the intermediate trees to the great dominant top 

 story the trees that reach up into the open sunlight and lord 

 it over all the forest world. It is from these dominant trees that 

 man obtains his most valuable lumber. 



