Miron Elisha Hard

BY PROF. LAMBERT,

The American Spawn Co., St. Paul, Minn.GENERAL CONSIDERATIONS.—Commercially, and in a restricted sense, the term "mushroom" is generally used indiscriminately to designate the species of fungi which are edible and susceptible of cultivation. The varieties which have been successfully cultivated for the market are nearly all derived from Agaricus campestris, Agaricus villaticus, and Agaricus Arvensis. They may be white, cream or creamy-white, or brown; but the color is not always a permanent characteristic, it is often influenced by surrounding conditions.

Mushrooms are grown for the market on a large scale in France and in England. It is estimated that nearly twelve million pounds of fresh mushrooms are sold every year at the Central Market of Paris. A large quantity of mushrooms are canned and exported from France to every civilized country. This industry has recently made remarkable progress in the United States, and fresh mushrooms are now regularly quoted on the markets of our large cities. They are sold at prices ranging from twenty-five cents to one dollar and fifty cents per pound, according to season, demand and supply.

Figure 498.—Mushroom Beds in a Cellar.

ESSENTIAL CONDITIONS.—Mushrooms can be grown in any climate and in any season where the essential conditions may be found, obtained or controlled. These conditions are, first, a temperature ranging from 53° to 60° F., with extremes of 50° to 63°; second, an atmosphere saturated (but not dripping) with moisture; third, proper ventilation; fourth, a suitable medium or bed; fifth, good spawn. It may be seen that in the open air, these conditions are rarely found together for any length of time. It is therefore necessary, in order to grow mushrooms on a commercial basis, that one or more of these elements be artificially supplied or controlled. This is usually done in cellars, caves, mines, greenhouses, or specially constructed mushroom houses. A convenient disposition of the shelves in a cellar is shown in Figure 498. A large installation for commercial purposes is shown in Figure 500, and a specially constructed cellar is shown in Figure 499. Where abandoned mines, natural or artificial caves are available, the required atmospheric conditions are often found combined and may be uniformly maintained throughout the year.

TEMPERATURE.—Within the limits prescribed, the temperature should be uniform throughout the growth of the crop. When too cold, the development of the spawn will be retarded or arrested. A high temperature will favor the development of molds and bacteria which will soon destroy the spawn or the growing crop. The cultivation of the mushroom, as a summer crop, is therefore greatly restricted. As a fall, winter or spring crop it may be grown wherever means are at hand to raise the temperature to about 58° F. Many florists are utilizing the waste space under the benches for that purpose; they have the advantage of being able to use the expended material of mushroom beds in growing flowers.

MOISTURE.—Moisture is an important factor in the cultivation of the mushroom, and demands intelligent application. The mushroom requires an atmosphere nearly saturated with moisture, and yet the direct application of water on the beds is more or less injurious to the growing crop. It is therefore essential that the beds, when made, contain the requisite amount of moisture, and that this moisture be not lost by excessive evaporation. They should be protected from a dry atmosphere or strong draughts. Where watering becomes necessary, it should be applied in a fine spray around the beds with a view of restoring the moisture to the atmosphere, and on the beds after the mushrooms have been gathered.

VENTILATION.—Pure air is essential to a healthy crop. Provision should therefore be made for a gradual renewal of the air in the mushroom house. However, draughts must be avoided as tending to a too rapid evaporation and cooling of the beds, an unfortunate condition which cannot thereafter be entirely remedied.

THE BEDS.—The most common type of beds is known as the "flat bed." It is made on the floor or on shelves as shown in the illustrations. It is usually about 10 inches deep. Another type, principally used in France, is known as the "ridge bed," and requires more labor than the flat bed. The mushroom house and shelves, if used, should be frequently disinfected and whitewashed in order to avoid danger from insects and bacteria. The preparation of the beds and subsequent operations will be shown in connection with the other subjects.

PREPARATION OF THE MANURE.—The best manure is obtained from horses fed with an abundance of dry and nitrogenous food. The manure of animals fed on greens is undesirable. Growers do not all follow the same method of fermenting or composting the manure. When first unloaded, the manure is left in its original state for a few days. It is then piled in heaps about three feet deep and well pressed down. In this operation the material should be carefully forked and well mixed, and wherever found too dry, it should be lightly sprinkled. It is allowed to remain in that condition for about six days when it is again well forked and turned. In the latter operation it receives an additional light sprinkling; the dry portions are turned inside in order that the whole mass may be homogenous and uniformly moist, and the heap is again raised to about three feet. About six days later the operation is repeated, and in about three days the manure should be ready for the beds. It is then of a dark brown color mixed with white, free from objectionable odor. It is unctuous, elastic and moist, though not wet, and should not leave any moisture in the hand.

Of course, the above rules are subject to modification according to the condition of the manure, its age and previous handling.

SPAWNING.—The manure, having been properly composted, is spread evenly on the floor or shelves and firmly compressed in beds about ten inches in depth. The temperature of the bed is then too high for spawning and will usually rise still higher. It should be carefully watched with the aid of a special or mushroom thermometer. When the temperature of the beds has fallen to about 75° or 80°, they may be spawned. The beds must be spawned when the temperature falls, never when it rises. The bricks of spawn are broken into eight or ten pieces, and these pieces are inserted from one to two inches below the surface, about nine to twelve inches apart. The bed is then firmly compressed. An advantage is found in breaking and distributing the spawn over the surface of the bed a few days before spawning; this allows the mycelium to absorb some moisture and swell to some extent. If the bed is in proper condition it should not require watering for several weeks.

CASING THE BEDS.—As soon as the spawn is observed to "run," or from eight days to two weeks, the beds are "cased" or covered with a layer of about one inch of light garden loam, well screened. The loam should be slightly moist, and free from organic matter. The beds should now be watched and should not be allowed to evaporate or dry out.

PICKING.—Mushrooms should appear in from five to ten weeks after spawning, and the period of production of a good bed ranges from two to four months. In picking the mushrooms an intelligent hand will carefully twist it from the soil and fill the hole left in the bed with fresh soil. Pieces of roots or stems should never be allowed to remain in the beds, otherwise decay might set in and infect the surrounding plants. A good mushroom bed will yield a crop of from one-half to two pounds per square foot. Mushrooms should be picked every day or every other day; they should not be left after the veils begin to break.

For the market the mushrooms are sorted as to size and color, and packed in one, two or five-pound boxes or baskets. Since they are very perishable, they must reach the market in the shortest time.

OLD BEDS.—It is not practicable to raise another crop of mushrooms in the material of an old bed, although this material is still valuable for garden purposes. The old material should be entirely removed, and the mushroom house thoroughly cleaned before the new beds are made. If this precaution be omitted the next crop may suffer from the diseases or enemies of the mushrooms.

SPAWN.—The cultivated mushroom is propagated from "spawn," the commercial name applied to the mycelium; the term "spawn" includes both the mycelium and the medium in which it is carried and preserved. Spawn may be procured in the market in two forms, flake spawn and brick spawn. In both forms the mycelium growth is started on a prepared medium mainly consisting of manure and then arrested and dried. The flake spawn is short-lived by reason of its loose form, in which the mycelium is easily accessible to the air and destructive bacteria. It deteriorates rapidly in transportation and storage and can only be used to advantage when fresh. Growers, especially in the United States, have therefore discarded it in favor of brick spawn, which affords more protection to the mycelium and can be safely transported and stored for a reasonable period.

Until recently the manufacturer of spawn was compelled to rely entirely upon the caprice of nature for his supply. The only method known consisted in gathering the wild spawn wherever nature had deposited it and running the same into bricks or in loose material, without reference to variety. Neither the manufacturer nor the grower had any means of ascertaining the probable nature of the crop until the mushrooms appeared.

PURE CULTURE SPAWN.—The recent discovery of pure culture spawn in this country has made possible the selection and improvement of varieties of cultivated mushrooms with special reference to their hardiness, color, size, flavor and prolificness, and the elimination of inferior or undesirable fungi in the crop. The scope of this article precludes a description of the pure culture method of making spawn. It is now used by the large commercial growers and has in many sections entirely superseded the old English spawn and other forms of wild spawn. As now manufactured it resembles much in appearance the old English spawn (see Figure 501). Some remarkable results have been obtained by the use of pure culture spawn. We illustrate a cluster of fifty mushrooms on one root grown by Messrs. Miller & Rogers, of Mortonville, Pa., from "Lambert's Pure Culture Spawn" produced by the American Spawn Company, of St. Paul, Minn. (Figure 502). Several promising varieties have already been developed by the new method, and can now be reproduced at will. Figure 503 is a good illustration of Agaricus villaticus, a fleshy species in good demand. Figure 504 shows a bed of mushrooms grown from pure culture spawn in a sand rock cave, using the flat bed.

HOW TO COOK MUSHROOMS.—To the true epicure there are but four ways of cooking mushrooms—broiling, roasting, frying them in sweet butter and stewing them in cream.

In preparing fresh mushrooms for cooking, wash them as little as possible, as washing robs them of their delicate flavor. Always bear in mind that the more simply mushrooms are cooked the better they are. Like all delicately flavored foods, they are spoiled by the addition of strongly flavored condiments.

Broiled Mushrooms.—Select fine, large flat mushrooms, and be sure that they are fresh. If they are dusty just dip them in cold salt water. Then lay on cheese cloth and let them drain thoroughly. When they are dry cut off the stem quite close to the comb. Or, what is better, carefully break off the stem. Do not throw away the stems. Save them for stewing, for soup or for mushroom sauce. Having cut or broken off the stems, take a sharp silver knife and skin the mushrooms, commencing at the edge and finishing at the top. Put them on a gridiron that has been well rubbed with sweet butter. Lay the mushrooms on the broiling iron with the combs upward. Put a small quantity of butter, a little salt and pepper in the center of each comb from where the stem has been removed and let the mushrooms remain over the fire until the butter melts. Then serve them on thin slices of buttered and well browned toast, which should be cut round or diamond shape.

Serve the mushrooms just as quickly as possible after they are broiled, as they must be eaten when hot. So nourishing are broiled mushrooms that with a light salad they form a sufficient luncheon for anyone.

Fried Mushrooms.—Clean and prepare the mushrooms as for broiling. Put some sweet, unsalted butter in a frying pan—enough to swim the mushrooms in. Stand the frying pan on a quick fire, and when the butter is at boiling heat carefully drop the mushrooms in and let them fry three minutes, and serve them on thin slices of buttered toast.

Serve a sauce of lemon juice, a little melted butter, salt and red pepper with fried mushrooms.

Stewed Mushrooms.—Stewed mushrooms after the following recipe make one of the most delicious of breakfast dishes: It is not necessary to use large mushrooms for stewing—small button ones will do. Take the mushrooms left in the basket after having selected those for broiling, and also use the stems cut from the mushrooms prepared for boiling. After cleaning and skinning them put them in cold water with a little vinegar, and let them stand half an hour. If you have a quart of mushrooms, put a tablespoonful of nice fresh butter in a stewpan and stand it on the stove. When the butter begins to bubble drop the mushrooms in the pan, and after they have cooked a minute season them well with salt and black pepper. Now take hold of the handle of the stewpan and, while the mushrooms are gently and slowly cooking, shake the pan almost constantly to keep the butter from getting brown and the mushrooms from sticking. After they have cooked eight minutes pour in enough rich, sweet cream to cover the mushrooms to the depth of half an inch, and let them cook about eight or ten minutes longer. Serve them in a very hot vegetable dish. Do not thicken the cream with flour or with anything. Just cook them in this simple way. You will find them perfect.