SPAWN-MAKING 



made. One may therefore get specimens 

 from the fields, or the woods, or from the 

 beds of mushroom growers. In another 

 chapter it is shown that there are numerous 

 strains and varieties of the cultivated mush- 

 room. Whether these varieties vary as to 

 color, whether they differ in quality or pro- 

 ductiveness, or show diversity in other char- 

 acters, the method permits a perpetuation of 

 the kinds which promise something of in- 

 terest or of value. Any individual differ- 

 ence indicating the possibility of a perma- 

 nent desirable departure may be selected, 

 and henceforth, if this quality is stable, this 

 particular characteristic may be propa- 

 gated. It is believed that this method may 

 be fully relied upon for further progress 

 in selective mushroom growing. 



At one time there was the feeling that 

 even with the tissue culture method there 

 might be more or less "running out." I 

 have, however, tested for five years one 

 strain by continuous propagation from sea- 

 son to season through tissue cultures, and 



103 



