MUSHROOM GROWING 



celium of Agaricus campestris grows quite 

 well upon synthesized media, that is, nutri- 

 ent media prepared from known chemical 

 substances, such as the ordinary nutrient 

 ^^fertilizer" salts with the addition of 

 casein, peptone, etc. In fact, laboratory ex- 

 periments indicate that all of the nitrogen 

 may be supplied as inorganic salts, if a suit- 

 able organic compound as a source of car- 

 bon is furnished. 



Is it possible to improve the manure by 

 the addition of mineral nutrients, or fertil- 

 izers? While experiments thus far seem to 

 indicate that cotton seed meal fermented 

 with manure will increase the yield, the ex- 

 periments with mineral nutrients have been 

 in the main contradictory, the addition of 

 phosphorous (as a phosphate), and of lime, 

 however, being often advantageous. The 

 variable quality of manure and spawn, and 

 thus far the impracticability of co-operating 

 with extensive growers, have prevented an 

 adequate study of nutrition on a practical 

 basis, although much attention has been 



60 



