SPAWN-MAKING 



much employed. It is said that in the vi- 

 cinity of Paris some persons make a business 

 of searching for this virgin spawn, which 

 they sell to the growers at a high figure. It 

 is claimed that they become so adept in de- 

 tecting the differences in the character of 

 growth, the quality of odors, etc., that they 

 can distinguish not only Agaricus campes- 

 tris, but also some of its varieties. 



It might be asked: What is the neces- 

 sity for virgin spawn? Why not transfer 

 the spawn continually from one bed to an- 

 other? The answer to these questions is 

 found in the fact that experience shows this 

 to be an unprofitable method if carried too 

 far. The feeling is that a practice of this 

 kind results in a complete '^running-out" or 

 deterioration of the spawn if persisted in 

 for about three years. To a limited ex- 

 tent the idea of transfer is applicable, as we 

 shall see in a moment, but under certain re- 

 strictions. It is to be regretted that defi- 

 nite experiments are lacking regarding the 

 extent to which successive propagation is 



95 



