TEMPERATURE AND MOISTURE. 



31 



Table VII. — Resulfi^ of tc-stx of acUJity and aJkaUnUij. 



Medium. 



4 drops EHO 



•2 drops KHO 

 1 drop KHO . 



Control 



Nature of 



stable 

 compost. 



[Fresh .. 



Rotted - 



fFresh .. 



JRotted . 

 (Fresh .. 

 iRotted . 

 Fre&h .. 



Extent of growth. 



Agaricus 

 campestris. 



Calvatia cya- 

 thiforme. 



Very slight 



Slight do 



Very slight . 



1 drop acid- 



iRotted . 

 2dropsacid_ :{^^; 



1 good, 1 



fair. 

 Very good . 



Good 



Very good . 

 1 very good, 



1 fair. 

 Very slight 



1 contami- 

 nated. ] 

 very good 



Very slight 



do 



do 



1 none , 1 

 slight. 



None... 



Very slight . . 



None 



1 good, 1 none 



Contamina- 

 ted. 



1 slight, 1 

 good. 



Very slight . . 



do 



Very good . . . 



Coprinus CO- ICoprinusatra- 

 matus. mentarius. 



Slight..,— .. 



Very slight.. 



1 very good, 1 



excellent. 

 Very good . . . 



Excellent 



do 



do 



None 



Excellent . 



do. 



.....do. 

 None.. 



1 good, 1 very 

 slight. 



Contamina- 

 ted. 



Very slight. 



Good 



Very good. 

 Excellent. 

 Very slight. 



None. 



Very slight. 



Do. 

 Do. 

 Do. 



TEMPERATURE AND MOISTURE. 



P The temperature factor is, next to that of good spawn, perhaps the 

 most important in mushroom growing. It has been frequently 

 stated that mushroom growing is not profitable when the temperature 

 may not be maintained more or less continuously at from 50° to 00° F. 

 It is very probable that the exact temperature which may be con- 

 sidered an optimum will vary somewhat in different sections of 

 the country. It will be noted later in detail that tlie temperature 

 factor acts not so directly upon the growth of the spawn or the produc- 

 tion of mushrooms as indirectly to render some other conditions of the 

 environment injurious. It is best to consider that in practice the op- 

 timum temperature for mushroom growing varies from 53° to 58° F. 

 When the matter of temperature was first under consideration, 

 a series of pure cultures of Agaricus caifnpeHtrh was placed at 

 diii'erent temperatures in the laboratory in order to determine the 

 rapidity of growth. It was soon found that a temperature above 

 60° F. and, indeed, as high as from 80° to 85° F., was much more 

 favorable to rapid growth than a lower temperature, provided, 

 of course, that the higher temperature did not encourage a too 

 rapid drying out of the culture. It was soon dehnitely ascer- 

 tained that the conditions of pure-culture growth are essentially 

 different from those attending the growth of mushroom spawn in 

 the bed. This was perhaps best indicated by comparing spawn 

 grown in j)ots at 85° F. under impure conditions with similai' 

 spawn grown at 50° F. At the former temperature, even though 

 the conditions of moisture were properly maintained, there was 

 little or no growth. Foreign fungi, molds, and bacteria, as well 

 as insects, were, however, abundant. At the lower tem])erature there 

 was little or no evident appearance of other fungi, molds, or insects; 

 G829— No. 85—05 M 3 



