35 



During the past two years the Bureau of Plant Industry at Washington 

 has attempted to improve the quality of spawn and methods of growing 

 mushrooms. It is anticipated that the results of this work will appear 

 subsequently in a special publication, and it is expected that much 

 valuable information resulting from research upon this subject will be 

 available and will materially assist mushroom growers in their business. 



How Mushrooms are grown. 

 The common mushroom of the market (Agaricus Cnmpestris) grows 

 almost everywhere out of doors. It is readily detected by those familiar 

 with mushrooms, and especially by foreigners who have spent their 

 early life in Europe, where considerable more attention is given to 

 edible fungi than in America. It is a matter of common observation in 

 summer to see Italians gathering various edible mushrooms in pastures. 

 Mushrooms frequently come up by 

 themselves in greenhouses under 

 the benches where manure and 

 potted soil is stored AYe have 

 gathered frequently many speci- 

 mens thriving in such localities. 

 When mushrooms are grown for 

 the market on a commercial basis 

 it is essential that all of the con- 

 ditions be made as desirable as 

 possible for their growth and de- 

 velopment, in order that a large 

 and profitable crop may be ob- 

 tained. It is necessary that a uni- 

 form degree of temperature be 

 maintained, and that the crops be ^"^- 3. — A group of mushrooms (Agaricus 



^ Campestris) . 



secluded from drafts and sunshine. 



Total darkness, however, is not absolutely necessary, since mushrooms 

 grow well in diffuse light. Uniform temperature and moisture con- 

 ditions are more likely to exist in dark places, and it is for this reason 

 that mushrooms are grown in the dark. Those who gi'ow mushrooms 

 commercially make use of cellars, barns, sheds, tunnels and space under 

 greenhouse benches, etc., as well as in specially constructed mushroom 

 houses. It is desirable, however, to have a tolerably dry foundation for 

 a mushroom bed. The conditions of a cellar can be made suitable for 

 mushroom growing, especially for amateurs who wish to go into the 

 business on a small scale. By partitioning off a portion of the cellar 

 and closing up the windows, more constant and uniform conditions can 

 be obtained. Space under greenhouse benches can be made especially 

 suited to nuishroom culture, and many growers take advantage of this 

 space for their propagation. 



Conditions adapted to Mushroom growing. 

 Soil. — The most suitable soil conditions for mushroom culture con- 

 sists in supplying the beds with plenty of good horse manure, mixed 



