MUSHROOMS 415 



it is not feasible or practicable for every grower to pro- 

 duce his own spawn. Those who are interested in this 

 phase of the industry should study Duggar's "Mushroom 

 Growing," Chapter VIII. It is gratifying, however, that 

 there are reliable American firms from whom pure cul- 

 ture spawn may be obtained at reasonable prices, so that 

 no one need take chances in planting ordinary commercial 

 spawn, whether it is made in the United States or in 

 foreign countries. Growers will do well to make a 

 thorough investigation of the sources of good spawn 

 before making purchases. Different varieties may be 

 obtained and tested just as gardeners test different sorts 

 of tomatoes or lettuce. 



The pure cultures are generally sold in the usual 

 commercial brick forms, as seen in Fig. 152. The bricks 



Fig. 152. Drying bricks of mushroom spawn. 



measure about 5^2 by 8y 2 by \y 2 inches. They pack 

 readily for shipment and are easily broken for spawning 

 the beds. It is exceedingly important to use fresh spawn. 

 That which is a year old seldom gives good results. 

 Duggar recommends that growers use spawn not more 

 than six or eight months old, and they will do well to 



