338 BRAUN 



ondary forest) as made up of a vast number of intergrading communities. 

 Some of the communities are developmental, others climax in nature, some 

 are very local in occurrence and extent, others recur frequently over consid- 

 erable geographic extent. The developmental communities give clues to 

 trends. Those climax communities which are limited to specific sites, more 

 or less extreme for their region, illustrate the great range of types possible in 

 a region. Those climax types which recur again and again, represented by 

 similar though individually different communities, are the ones which can 

 be classified into the major associations of the Deciduous Forest and are 

 the ones which best illustrate history and development of that forest through 

 the long ages of its existence. 



LITERATURE CITED 



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6:89-149. 

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— . 1942. Forests of the Cumberland Mountains. Ecol. Monog. 12:413-447. 

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