EXPERIMENT STATION BULLETINS. 



605 



Plate VI 



Michigan Technical Bulletin No. 53 







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Plate VI. Fig. 1. (Top) Showing the relation of temperature to mycelial 

 growth. 

 Fig. 2. The effect of air on root attacks. The plant at the 

 left was not inoculated; the middle one was inoculated and 

 supplied no air; the plant on the right was inoculated sup- 

 plied air. Note the scarcity of smaller roots' and the diseased 

 condition of the larger ones. 



