654 FIELD AND GARDEN PRODUCTS 



tibility for the commercial production of mushrooms. A thorough, 

 study should also be made of open air conditions. In the construc- 

 tion of special mushroom houses any one of a variety of plans may 

 be followed, and the selection of the style will depend, of course, 

 upon its cheapness and efficiency in the particular locality. 



Preparation of the Manure. It should be borne in mind that 

 while there are many methods leading to failure there are a number 

 leading to success. In fact, persons succeed in mushroom growing 

 by methods which seem absolutely different. It is essential that the 

 physiological conditions of growth be understood, and then good 

 judgment must be depended upon. 



In the growing of mushrooms for commercial purposes, the 

 beds should be constructed of stable manure which has been fer- 

 mented or composted. Many experiments have been made looking 

 toward the substitution of other composts or waste products for stable 

 manure, but nothing has yet been found which may be more highly 

 recommended. Fresh manure should be obtained, and this should 

 include the litter used for bedding the animals, unless the latter 

 consists of coarse weeds. It is a great mistake, in a commercial 

 way, to attempt to use manure free from straw. Again, stable ma- 

 nure which has been well trampled is nearly always well preserved, 

 and is frequently much richer than any other kind. 



The manure should be piled in heaps about 3 feet deep when 

 well pressed down with the fork, and these piles may be of con- 

 siderable extent. It should be watered until well moistened through- 

 out, but not drenched. In the course of four or five days or a week 

 it will be necessary to fork over or "turn" the manure. A second 

 turning will be required usually in from seven to ten days, and it 

 may be necessary to water again if the material used has suffered 

 considerable drying out. If well pressed down and merely moist, 

 the manure will not burn and, moreover, there will be no tendency 

 for a sour fermentation to become established. In from fifteen to 

 twenty-one days, depending upon the conditions, the temperature 

 will begin to fall, the violence of decomposition will begin to show 

 a subsidence, and the compost \yill be ready for the construction of 

 the beds. The bacteria of rapid decay will become less and less 

 abundant, and finally, when the beds are prepared as subsequently 

 described, the spawn will be able to grow in spite of the bacteria 

 present. 



It is the custom with some growers to mix a small quantity of 

 loam, about one-fourth, with the manure. This enables one to use 

 the manure earlier; and, indeed, under such circumstances it may 

 sometimes be used with but little or no composting. Nevertheless, 

 the majority of growers have obtained greater success by the use 

 of the manure alone. Very well rotted compost should not be used 

 in mushroom growing if large and solid mushrooms are desired. 

 When sawdust or shavings are employed for bedding the animals, 

 the composting may require a somewhat longer period. 



The manure is always ready for the construction of beds when 

 the above conditions have been fulfilled, or when nearly all objec- 



