CULTIVATION OF MUSHROOMS. 253 



Garden soil or rich loam is added, say at the first time the manure 

 is turned while it is fermenting. Then, some time later during the 

 process of fermenting, another admixture of soil is added. The total 

 amount of soil added is usually equal to about one-fifth of the bulk 

 of the manure. 



As this material, formed of the manure with an admixture of soil, 

 is placed in the beds it is distributed much in the same manner as 

 described for the making of flat beds in caves or tunnels. Usually, 

 however, if there is coarse material which was separated from the 

 manure at the first sorting, this without any mixture of soil is placed 

 in the bottom of the bed, and then the manure and soil is used for 

 the bulk of the bed above. This coarser material, however, is not 

 always at hand, and in such cases the beds are built up from the 

 bottom with the mixture of manure and soil. The depth of the 

 material in the beds in these houses varies according to the experi- 

 ence of the operator. Some make the beds about eighteen inches in 

 depth, while others do not make the beds more than eight or ten or 

 twelve inches in depth. Where there are tiers of beds, that is, one 

 bed above the other, very often the lowest bed, the one which rests 

 directly upon the ground, is made deeper than the others. 



While it is the general custom to use material consisting of an 

 admixture of manure and soil in the proportions described, this cus- 

 tom is not always followed. In the case of the beds which are 

 made up in the summer for the fall and early winter crop, soil, being 

 easily obtained at that season of the year, is mixed with the manure. 

 Some growers, however, in making the beds in midwinter for the 

 spring crop, do not use any soil since it is more difficult to obtain it 

 at that season. In such cases the beds are made up of manure 

 alone. The experience in some cases shows that the crop resulting 

 from this method is equally as good as that grown where soil has 

 been added. In the experience of some other growers a bin of soil 

 is collected during the summer or autumn which can be used in the 

 winter for mixing in with the manure and making the beds for the 

 spring crop. Where sod is used this is collected in pastures or 

 fence rows in June, piled, and allowed to rot during the summer. 



In distributing the material in the beds, the methods of packing 

 it vary according to the wishes or experience of the grower. It is 

 often recommended to pack the material very firmly. The feeling 

 that this must be packed very firmly has led to the disuse of beds 

 in tiers by some, because it is rather difficult to pack the material 

 down very firmly where one bed lies so closely above another. 

 Where the practice is followed of packing the material very firmly in 



