General. Wood valuable but the supply is limited and the tree 

 a slow grower; it is also an upper slope type and sometimes quite inac- 

 cessible. Silvicultural treatment, -more valuable than amabilis fir and 

 black hemlock; therefore to be preferred on upper slope type. Restrict 

 to h gher altitudes because it grows too slowly to compete with its lower 

 associates. 



ANGIOSPERMS OR "COVERED SEED" TREES, 

 TREATED AS A CLASS. 



Also called the broad-leaved trees, deciduous 

 trees, and hardwoods. 



Size. In general inferior to the gymnosperms. The tulip tree is 

 one of the largest representatives in North America. 



Growth. More rapid, but less persistent and shorter lived than the 

 gymnosperms. 



Root System. Generally deeper than gymnosperms. Ranges 

 from deep rooted oaks to shallow hard maple. 



Bole. Divided. 



Crown. Generally spreading; deciduous except in the south. 



Tolerance. Less tolerant than the gymnosperms. Varies from the 

 very tolerant hard maple and beech to the intolerant oaks and ashes. 



Wood. The hardwoods are relatively heavier, harder and stronger 

 than the softwoods. Range from soft, light, weak basswood, poplar 

 and tulip to the. heavy, hard, strong oaks and hickories. Durability is 

 less than the gymnosperms. Ranges from the durable white oak to the 

 perishable poplar. 



Reproduction. Seeds generally larger and heavier than those of 

 the gymnosperms. Reproduction by coppice gives them in many cases 

 a great advantage in pre-empting the ground after a fire. The ability to 

 coppice varies from the vigorously coppicing long-lived stocks of oak and 

 chestnut to the weakly sprouting and short-lived stocks of beech and 

 birch. 



Range. From the tropics to the Arctic Circle timber line, and from 

 sea-level to the mountain timber line, but in the latter case less common 

 at the upper limits than the gymnosperms. Optimum in Tropical to 

 South Temperate Zones. Deciduous forest proper, optimum in the Ohio 

 and lower Mississippi basins and in Japan. 



Soil. Inhabit better soils and are more mesophytic than gymno- 

 spcrm*. ranging from the exacting sugar maple to the scrub oaks and 

 willo 1 



Association. Generally mixed individually or in groups. Mixture 

 much more complex than with gymnosperms. 



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