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UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 700 



Contribution from the Forest Service 

 HENRY S. GRAVES, Forester 



Washington, D. C. 



PROFESSIONAL PAPER 



October 14, 1918 



CLIMATE AND PLANT GROWTH IN 



CERTAIN VEGETATIVE 



ASSOCIATIONS 



By 



ARTHUR W. SAMPSON, Plant Ecologist 



Forest Service 



CONTENTS 



Page 



The Problem . 1 



The Experiments 3 



Preparation of Plants 4 



Planting 5 



Measurement of Plants 14 



Experimental Error 14 



Measurement of Physical Factors ... 16 



Page 

 Comparison of the Climatic Characteris- 

 tics of the Three Plant Types . . . . 27 

 Correlation Between Growth and En- 

 vironmental Factors ....... 41 



Summary 69 



Conclusions *71 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



191$ 



