28 FIRST BOOK OF FORESTRY 



so far have been growing on dry land, are now made 

 to stand in water ; and in almost all cases they die, even 

 if the dam is closed for but a few months of the year. 

 Evidently these forest trees do not endure immersion of 

 their roots ; too much water kills them. 



In the valleys, or " bottoms," of the Santee and other 

 rivers of the South, floods or freshets are produced by 

 heavy rains in the mountains at the heads of these 

 streams. Where we can walk dry-footed to-day we can 

 boat on ten feet of water to-morrow. These freshets last 

 from one to three weeks and, during this time, cover 

 entirely all young trees not tall enough to project above 

 the water. And yet the forests of these bottoms are 

 among the most luxuriant; there are many kinds of 

 trees, and the trees grow to large size. 



It would seem, then, that in these fertile bottoms of the 

 South many different kinds of trees and shrubs have 

 learned to endure periodical, complete or partial immer- 

 sion of several weeks duration. 



The hundreds of large and small swamps of our north- 

 ern forests are generally stocked with forests of tamarack, 

 cedar, and occasionally spruce. Generally these cedar and 

 tamarack swamps are monotonous ; the trees are small, 

 the stands dense. The cedar swamps of New Jersey, the 

 numerous cypress swamps of the Carolinas, Florida, and 

 the Gulf States resemble our northern swamps, except that 

 we have here a different set of trees and trees of larger 



