352 THE POPULAR SCIENCE MONTHLY 



evidence of the minimum age of such lakes. 10 It prefers soil that is 

 rather rich, either from the amount of mineral plant food in the strata 

 penetrated by its roots, or from alluvium deposited by streams. 



The regions where this species grows have a mean temperature of 

 about 53°-75°, a growing season of 180 to 360 days, and an average 

 annual rainfall of 38 to 65 inches. It is successfully cultivated, how- 

 ever, not only in New York or even farther north of its natural range, 

 but at the same time in ordinary dry soil of parks and streets. 17 



The cypress swamps are pretty well protected from fire most of the 

 time by the wetness of the soil or the absence of inflammable material 

 on the ground, but occasionally in a very dry season fire gets into the 

 edge of such a swamp from the neighboring uplands and kills some of 

 the trees, whose thin bark renders them rather sensitive. 



The wood of our cypress, like that of the Old World tree of quite 

 different appearance which bore the same English name long before ours 

 was discovered by civilized man, is very durable and easily worked, and 

 therefore cut in large quantities for shingles and other articles which 

 are to be exposed to the weather or placed in contact with the soil. The 

 last census reports 955,635,000 feet of cypress as having been sawed in 

 1909, nearly two thirds of this amount coming from Louisiana. Next 

 in order were Florida, Arkansas, Mississippi, South Carolina, North 

 Carolina, Missouri and Georgia. (Some of this amount, however, 

 possibly 10 per cent., should be credited to the other species of cypress 

 discussed a little farther on.) The soil in which cypress is found is 

 usually too wet for cultivation and not easily drained, so that in spite 

 of the tree's slow growth and the rapid rate at which it is being cut the 

 supply will probably not be exhausted for many years. 



The Long-leaf Pine (Pinus palustris), also known as yellow or 

 Georgia pine, extends through the coastal plain from extreme southern 

 Virginia to the vicinity of the Caloosahatchee Eiver in Florida and the 

 Trinity Eiver in Texas, and also inland to the mountains of Georgia 

 and Alabama, nearly 2,000 feet above sea-level. (It almost meets the 

 white pine in Georgia.) In the greater part of its range it is the most 

 abundant tree, and there are or have been many places where it is the 

 only tree in sight. It probably was originally, and may be even yet, 

 the most abundant tree in eastern North America. The long-leaf pine 

 forests, or southern pine-barrens, differ from most others in their open 

 park-like character. Even in a virgin forest of this kind one can usually 

 see about a quarter of a mile in every direction; and the ground is 

 carpeted with wire-grass or other coarse grasses, or with low shrubs. 



is See Science, II., 36: 760-761, November 29, 1912. 



1 7 In such situations its characteristic "knees," the tops of which in a state 

 of nature seem to indicate the greatest height of water to which the tree is ac- 

 customed, are developed on a very small scale if at all. 



