MISCELLANEOUS CROPS 653 



unsafe to attempt to grow mushrooms on a commercial basis, accord- 

 ing to present knowledge of the subject, at a temperature much less 

 than 50 or greater than 63 F. Any severe changes of temperature 

 retard growth, or else act injuriously, and many changes of tem- 

 perature would entirely destroy the profits of the mushroom crop. 

 From this it is evident that in many places mushrooms may not 

 be grown as a summer crop. With artificial heat they may be 

 grown almost anywhere throughout the winter. Moreover, it is 

 very probable that in this country open-air culture must be limited 

 to a few sections, and restricted, commercially at least, to a single 

 season. 



A second important factor is that of moisture. The place 

 should not be very damp, or constantly dripping with water. Under 

 such conditions successful commercial work is not possible. A 

 place where it is possible to maintain a fairly moist condition of 

 the atmosphere, and having such capability for ventilation as will 

 cause at least a gradual evaporation, is, by general practice and by 

 the most extensive experimentation, shown to be necessary. With 

 too rapid ventilation and the consequent necessity of repeated ap- 

 plications of water to the mushroom bed no mushroom crop will 

 attain the highest perfection. 



Caves, Cellars, and Houses. They are used for growing mush- 

 rooms, because in such places only can the conditions of tempera- 

 ture and moisture be best regulated. Cold is less injurious to mush- 

 room beds than heat. The former renders the bed for a time un- 

 productive ; but the latter stimulates the spawn to too rapid growth, 

 which is usually followed by the production of unsalable mush- 

 rooms, or by the eventual death of the spawn, supposedly by damp- 

 ing off. 



Mushrooms may often be grown in a very simply constructed 

 shed or unused barn which will provide against any sudden changes 

 of the temperature, and when it is possible to employ artificial heat 

 the season for mushroom production in such structures may be 

 greatly extended. Cellars, are very commonly used in producing 

 mushrooms for, family use. Natural or artificial caves are of the 

 first importance, however, for commercial work, since the situation 

 of these below the surface will best insure a temperature through- 

 out almost the entire year more or less close to that which is desired. 

 In selecting caves or cellars, one should guard against the possibility 

 of flooding or of too much seepage water during a rainy season. 

 Perhaps the least satisfactory situation among those mentioned is 

 the greenhouse. Under ordinary circumstances it heats up too 

 readily during days of warm sunshine, and, unless special pre- 

 acutions are taken, it is not to be generally recommended for ama- 

 teurs. Nevertheless, during the fall and winter it is possible to 

 grow mushrooms under the benches or in any other unused space 

 with but very little outlay of money or labor. Cold frames may 

 also be used to good advantage during the autumn or spring. The 

 natural caves of this country and abandoned coal mines in some 

 sections should be further investigated with relations to their adap- 



