CONTENTS. 



Page. 



Introduction 9 



General considerations 10 



Market conditions 11 



Germination studies 12 



Review of earlier work _ _ 12 



Experimental work 14 



Tissue cultures 18 



Nutrition 23 



Growth on manure and other complex media 23 



Growth on chemically known media 26 



Tabulation of special results ' 26 



Acid and alkaline media 30 



Temperature and moisture 31 



Preparation of the compost 33 



Installation of beds 37 



Spawning and casing the beds 38 



Mushroom growing _. 39 



Experiments at Columbia, Mo 39 



Variability in mushrooms grown under different conditions 45 



The cultivation of various species of mushrooms. . . 46 



Cooperative experiments . 47 



Cave facilities in the United States 48 



Open-air culture 49 



Mushroom spawn making 52 



A ' ' chance ' ' method . 53 



A ■ ' selective ' ' method 53 



Pure-ciilture precautions 53 



The tissue- culture method 54 



The commercial process 55 



The vitality of mushroom spawn 58 



