, 



WEST VIRGINIA 



AGRICULTURAL EXPERIMENT STATION, 

 MORGANTOWN, W. VA. 



BULLETIN 56. APRIL, 1899. 



REPORT ON INVESTIGATIONS TO DETERMINE 

 THE CAUSE OF UNHEALTHY CONDI- 

 TIONS OF THE SPRUCE AND 

 PINE FROM J880-J893. 



BY A. D. HOPKINS. 



