MUSHROOM GROWING 



from 50"^ to 65° F. It is certain that mush- 

 room growing (as at present conducted) at 

 a temperature more or less continuously 

 above 60'' F., or below 50° F., is not com- 

 mercially successful; yet much depends 

 upon other factors than temperature. 



High temperature more injurious. With 

 respect to the extremes, however, it may be 

 said that the mushroom bed will not be ren- 

 dered useless by being heated to 70°, or 

 more, for brief periods, and it will withstand 

 a low temperature, or even being frozen for 

 a considerable period of time. The amount 

 of heat and the amount of cold which may 

 permanently injure the bed will be deter- 

 mined very largely by the extent of the 

 growth already made, and by the conditions 

 of moisture. Any severe changes, however, 

 either retard growth or act more injuriously. 

 As above suggested, a high temperature long 

 continued, say 72° F. for 24 hours, is fatal 

 to the pin heads and injurious to the spawn. 

 This eflfect, as will be shown later, is not 

 due to the fact that the mushroom spawn is 



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