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THE POPULAR SCIENCE MONTHLY 



out the aid of fire. All forests of it bear the marks of frequent ground 

 fires, which in some places come nearly every year. At the present 

 time, of course, most of the fires are of human origin, but those set by 

 lightning in prehistoric times could spread over much larger areas than 

 they do now, on account of the absence of clearings, roads, and other 



Puke Stand of Black Pine (Finns serotina) in the Dover Pocosin, Jones Co., 



North Carolina. August, 10^3. 



artificial barriers, so that the frequency of fire at any one spot may not 

 be much greater now than it was originally. A fire every year during 

 the lifetime of the tree would be likely to prevent its reproduction, but 

 in any area that escapes burning for a few years once in fifty years or so 

 there is opportunity for a new crop of trees. 



If fire were withheld too long the oaks and other hardwoods which 

 grow in the long-leaf pine regions would take possession of the ground 

 and gradually crowd the pine out, for its seedlings do not thrive in 

 shade. Proofs of this can be seen in many places in the coastal plain, 

 where fire is barred by the topography, as on bluffs bordering swamps, 

 or by water, as on islands and narrow-necked peninsulas. Such places, 

 in which the soil must have been originally much the same as in the 

 neighboring pine forests, are nearly always occupied by what is known 

 as "hammock" vegetation, consisting mostly of hardwood trees, which 

 make a rather dense shade and cover the ground with humus. 18 



is The idea that fire is essential to the long-leaf pine has been expressed 

 long ago by a few other observers in the south, but has never been generally ac- 



