RAISING OR KEEPING UP THE FOREST 51 



the coppice is managed on a thirty-year rotation. Rota- 

 tion in this sense simply means the age of the trees when 

 the woods are cut down, and does not mean, as in farming, 

 a certain succession of different kinds of crops, such as wheat, 

 corn, oats, and clover, to be repeated in the same order. 



The fact that in the northern pineries the burned-over 

 slash lands are commonly covered by a growth of young 

 poplar or aspen, and not by pine, has led some of the 

 woodsmen of those regions to believe that there existed a 

 natural rotation of forest crops resembling the rotation of 

 farm crops ; that pine could not follow pine, but that 

 poplar and pine always alternated with each other. As 

 a matter of fact, the poplar covers these " burns" because 

 all through these pineries there is produced every year an 

 abundance of poplar seed. Being extremely light, it is 

 carried by the wind for miles and thus covers the burns. 

 Moreover, the seeds of poplar and birch are the only tree 

 seeds which are at once strewn abundantly over the burns, 

 and both, especially that of the poplar, do well on this 

 freshly burned-over land. Thus it comes that the poplar 

 and birch thickets are the first to reclothe these burns. 



We have learned that in European coppice woods the 

 rotation is generally about fifteen to twenty-five years, 

 and, therefore, shorter than that of the ordinary New 

 Jersey coppice, which is usually thirty or forty years ; and 

 that it is generally not advisable to make the rotation in 

 coppice much longer than forty years, even for oak, which 



