PREFACE vii 



The facts and conclusions here presented, 

 based as they are on a short period of observa- 

 tion and a comparatively restricted number of 

 measurements, must of necessity be susceptible 

 of enlargement, and perhaps of correction also, 

 as the result of more extended investigations. 

 Meanwhile, observations and measurements 

 which may be forwarded to the address below 

 will be exceedingly welcome, whether they tend 

 to confirm these conclusions or to disprove them. 

 Any material bearing upon the contents of this 

 study, or upon any phase of the life, growth, or 

 utilization of the White Pine, will be very gladly 

 received. 



The motive which gave rise to this attempt, 

 in the minds of all those who have shared in 

 the work, was the desire to assist in making 

 clear the real nature of forestry, in exciting an 

 interest in the subjects with which it deals, in 

 stimulating others to similar research, and, 

 above all, in facilitating and hastening the gen- 

 eral introduction of right methods of forest 

 management, by which alone our forests can be 

 saved. 



GiFPORD PiNCHOT. 

 Grey Towers, Milford, Pa., 

 March 7, 1896. 



