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STATE BOARD OF AGRICULTURE 



THE ACTIVE SEASON OF GROWTH. 



The period of active growth of trees in Michigan is the six months from May to 

 October. The cold season both as regards temperature and precipitation of atmos- 

 pheric moisture has a small influence on forest growth. 



A table is here presented giving the mean rainfall in inches for the six mouths of 

 each year, and the monthly temperature for the year. 







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