MUSHROOM 



MUSHROOM 



2085 



to the special use to which it is put by temporary 

 partitions, false floors, or by other means which will 

 suggest themselves. In those cases in which cellars or 

 caves are used, it is important that there shall be good 

 ventilation. So-called "stagnant" air is almost as bad 

 in mushroom-growing as in greenhouse work. In such 

 air, moreover, the mushrooms will tend to become 

 long-stemmed and the caps will be relatively small. 

 The amount of ventilation will depend upon circum- 

 stances, but in all cases it should be sufficient so that 

 there will be a constant, but slight drying of the beds 

 from day to day, requiring occasional sprinkling. There 

 are probably only a dozen places in the United States 

 where mushrooms may be grown advantageously in 

 mushroom beds in the open, and this is primarily due 

 to the variability of the temperature, but partially also, 

 to the difficulty of maintaining the requisite humidity. 



Preparation and care of beds. 



When the stable-manure has been composted for a 

 period of eighteen to twenty days, it will have lost 

 practically all objectionable odor, the temperature will 

 probably have fallen to 120 to 130 C. (248 to 266 F.), 

 and the texture will be adhesive or oleaginous. In this 

 condition, it may be made into beds. The type of bed 

 commonly employed in the United States and England 

 is a flat bed from 6 to 8 inches deep, and from 2^4 to 4 

 feet wide, depending upon whether it is accessible from 

 one or from both sides. In France the ridge bed is more 

 commonly employed. Somewhat more labor is required 

 in the construction of the latter, but the surface area 

 is considerably increased. The ridge-bed system is 

 seldom employed when the beds are arranged hi tiers. 

 It is far more applicable to the growing of mushrooms 

 in caves or cellars. The use of flat beds in tiers, or hi 

 the nature of shelves, will often permit one to multiply 

 to the extent of four- or five-fold the amount of avail- 

 able space. 



The compost is thrown into the space to be occupied 

 by the bed, arranged as required, and immediately 

 "firmed." The beds should not be hammered down 

 with a wooden mallet as is the custom with some 

 growers. Usually the temperature of the bed rises after 

 the first day, and the maximum is promptly attained. 

 Within a few days the temperature will begin to fall 

 and the bed may be spawned at 70 to 75 F., with the 

 temperature on the decline. In no case should the 

 amateur grower attempt to spawn his beds when the 

 temperature is above 75 F. It does no harm at all to 

 spawn at 60 to 70 F., but a growth begins somewhat 

 more rapidly at the temperature first mentioned. 

 Within a week or so, the temperature should fall to 

 that which has been mentioned as normal for mush- 

 room-growing, that is, about 54 F. 



When brick spawn is used, each brick may be broken 

 into about twelve pieces, and one piece will be required 

 for each square foot of bed space. Insert each piece 

 from 1 to 2 inches below the surface, holding it with 

 one hand while pressing the compost firmly about it 

 with the other hand. In the course of about ten days 

 the new growth should become evident about each 

 piece of spawn, and when an examination of the bed 

 discloses this fact, the bed may be smoothed and again 

 firmed, or slightly compressed, such that a person 

 might stand on it without sinking in the substratum 

 more than from 1 to 2 inches. If there has been any 

 drying of the surface layers, the beds should be sprink- 

 led, and it is then ready for the "casing" of loamy soil. 

 A good casing soil is an ordinary light loam, but almost 

 any good garden soil is serviceable for this purpose. 

 The presence of a considerable amount of woods 

 mold in the soil is to be avoided. The soil is applied 

 evenly to a depth of 1 to 1^ inches, and it should be 

 firmed as applied. 



Subsequent to the casing, the beds will require no 

 attention except with respect to the regulation of 



temperature and moisture. The soil should be kept 

 constantly quite moist, but water should never be 

 applied copiously while the spawn is spreading. Em- 

 ploying good spawn, mushrooms should begin to appear 

 in six to seven weeks, although a longer period of time 

 may be required if sawdust or shaving compost has 

 been used. Under uniform conditions, mushrooms will 

 appear quite regularly all over the bed, and they will, 

 especially at first, have a tendency to come in flushes. 

 When the first flush has been picked, there may be an 

 interval for that bed of several days, or a week, before 

 a second flush will appear. 



In harvesting mushrooms, it is usually best to take 

 them before or just at the time that the veil begins to 

 break. At about this time they will have attained their 

 maximum weight, and they make a far better appear- 

 ance than later. The common method of harvesting 

 requires the operator to take hold of the cap firmly, 

 twisting it slightly, as a result of which the mushroom 

 is often removed from the bed without cutting. When, 

 however, the mushrooms grow in clusters, the assist- 

 ance of a knife is needed; and it is often possible to 

 remove those sufficiently developed without endanger- 

 ing the growth of smaller ones in the cluster. In pre- 

 paring the product for the market, the basal portion of 

 the stem is cut off, and the plant is brushed with a 

 medium-sized paint-brush so that it is made free from 

 soil-particles. The best markets require that the prod- 

 uct shall be graded into large, medium, small, and old 

 mushrooms. Small growers, however, can seldom afford 

 to adopt this system, and they should cut with such 

 regularity as will insure a fairly uniform size. 



Mushrooms, families of. 



The cultivated mushroom is one type of the Agari- 

 cacese, a family in which the spore-bearing, or fruit- 

 ing surface (hymenium) is in the form of leaf-like 

 plates, or gills. The spore prints of the fifty or more 

 genera of this family vary in color from near black 

 through all shades of brown and ochre to pure white. 



Agaricus campestris, the common cultivated mush- 

 room or field mushroom, has already been described. 

 It is important to note for this, as for all species of the 

 genus, the brown-black spores, the central stalk, the 

 characteristic ring or annulus, and the gills changing 

 from pink or light brown to brown-black free from the 

 stem. In general, A. campestris possesses a simple 

 ring, the stem is fairly uniform in diameter, and the cap 

 varies from a cream-color to various shades of brown 

 or gray-brown. The upper surface is usually smooth, 

 but with alternate wet and dry weather or, as a result of 

 the growth in rooms with variable artificial heat, it 

 may be broken into more or less diamond-shaped areas 

 exposing the white flesh. There are probably several 

 cultivated varieties of this species, but it is often 

 difficult to determine whether a given variety in cul- 

 ture belongs to this or to some related species. Three 

 trade forms based largely on color are generally 

 recognized, but within these color limits there are 

 undoubtedly many varieties. The three trade names 

 referred to are: "Alaska," relatively small, white or very 

 light gray forms; "Bohemia," large brown varieties, 

 one of which at least may be A. campestris; and "Col- 

 umbia," which is the name for the large cream-colored 

 forms which may apparently be referred to one of 

 several species. 



Agaricus arvensis, ordinarily known as the horse 

 mushroom, has much the same season and habitat as 

 A. campestris, and forms occur which seem to be inter- 

 grading. Typical forms of the horse mushroom are 

 larger and stouter than the field mushroom and dis- 

 tinguished from the latter by the possession of a double 

 ring. There is some diversity of opinion regarding 

 pileus (color) characters; but in any event there would 

 appear to be several varieties in cultivation which may 



