w 



V. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF PLANT INDUSTRY— BULLETIN NO. 85. 



B. T. GALLOWAY, Claie/ of Bureau. 



THE PRINCIPLES OF MUSHROOM GROOVING 

 AND MUSHROOM SPAWN MAKING. 



BY 



m 



B. M. DUGGAR, 

 Peofessor OF Botany in the University of Missouri, and 

 Collaborator of the Bureau of Plant Industry. 



VEGETABLE PATHOLOGICAL AND PHYSIOLOGICAL 

 INVESTIGATIONS. 



Issued November 15, 1905. 



WASHINGTON: 



government printing office. 



1905. 



