reprinted from Cyclopedia of American Horticulture, L.H. Bailey.

All but the die-hard scientists amongst us will find the first part of this material far too technical and scientific. You have permission to skip ahead to the subheading of Mushroom Culture if you wish. We reprint the ‘thick with the thin’ because if it doesn’t show up here likely it won’t show up elsewhere. This material was written at the beginning of the 1900s and should be qualified as such. This does not mean that we cannot find good information here, quite to the contrary. Please remember that mushrooms in the wild are not a thing to be taken lightly, there are a few out there which can cause death. LRM

Fig. 1440. The gardener’s Mushroom, Agaricus campestris.

While the word Mushroom is now often used as a general term for a large number of the higher fungi, chiefly those belonging to the Agaricini, it is by some limited to the common edible species in cultivation and which also grows spontaneously in lawns, pastures, etc. By others, the word is employed for all edible species, while toadstool is employed to designate poisonous species; such persons usually make an incorrect application of these terms to many of the plants. The word is probably derived from the French word “mousseron,” and is sometimes pronounced “mushroons,” or “musheroons” by English-speaking people in America. Mushroom and toadstool are sometimes used as synonymous terms, especially in speaking of the group as a whole. It is difficult, therefore, to give either a satisfactory definition of the word Mushroom, or satisfactorily to limit the range of forms for which the name may be used. In a horticultural sense it is applied to Agaricus campestris (Fig. 1440) in cultivation, and since that is the plant with which we are first interested here, we may proceed at once to a description of its form, structure, development, etc., and follow with briefer descriptions and comparisons of a few of the many species belonging to this large group.

Fig. 1441. Cultivated Mushroom, Agaricus campestris.

Form and Structure of Agaricus campestris. – The form of the common Mushroom is more or less umbrella-shaped, and is well represented in Fig. 1441. The prominent parts of the plant are the stem, with its ring (a); and the cap, with the gills on the under side. The cap, or pileus, as it is technically called, is the upper expended part, and varies from 2 to 4 or 5 inches in diameter. It is usually white in color, but forms occur both in the field and in cultivation in which the upper surface is more or less brownish, especially as the plants become old. The surface is usually smooth, though it often presents a silky texture from the numerous minute fungous threads or mycelium, the structural element of the entire plant. While the surface is smooth in a majority of specimens, many forms are more or less scaly, due to the fracture of the surface and separation of the numerous small areas, especially in the specimens with brownish caps. The “flesh” or “meat” of the cap is white. The stem, or stipe, is usually cylindrical, 1 – 3 in. long by ½ – ¾ in. in diameter, whitish in color, and nearly or quite solid. The “ring,” or annulus, forms a collar joined around the stem near the top. It is very delicate, easily rubbed off, and sometimes not present because the veil from which it is formed is torn in fragments as the cap opens out. The gills, or lamellae, on the under side of the cap are of great importance in showing relationship, and also probably in reproduction in the case of plants propagated under natural conditions, since they form the fruiting surface of the Mushroom. The gills are in the form of narrow, thin plates, shaped somewhat like a knife-blade, attached by one edge to the under side of the cap and radiating from a point near the stem out to the margin of the cap. The longest gills extend for this distance and mark off triangular areas, which are filled with successively shorter gills, all reaching the margin of the cap, so that the entire under surface of the cap is well covered with them. The surface of the gills is the fruiting surface of the plant, and this economy in the arrangement of the gills provides for a very large fruiting area. The color of the gills when the plant is very young is white. They soon, however, become pink in color, and as the plant ages become purplebrown or blackish in color, due to the immense number of spores borne on the surface. One can gain a good idea of the number of spores borne on a single plant by cutting a cap from a Mushroom, just at maturity, and placing it, gills downward, on a piece of white paper for a few hours. The spores fall from the gills and pile up in ridges, giving an exact print of the spaces between the gills.

Fig. 1442. Section of gill of Agaricus campestris, enlarged. tr: trama; sh: hymenium; b: basidium; st: sterigma; sp: spores.

The parts of the plants enumerated above are easily seen. Other important structural characters are seen with the aid of the microscope. A thin section across the gills when seen with the microscope show the structure as seen in Fig. 1442. The middle part of the gill is the trama. On either side of the trama is the subhymenium, composed of branches from the trama and forming short cells. The cells of the subhymenium in turn give rise to the basidia (basidium), club-shaped bodies, which form a palisade layer of cells over the entire surface of the gill. This palisade layer of the basidia forms the fruiting surface, or hymenium.

At the end of each basidium are either 2 or 4 slender, pointed processes, the sterigmata (sing. sterigma.) These bear each a single spore, the basidiospore. The usual number of sterigmata on the basidium in the Agaricini is 4; but in Agaricus campestris the number seems to vary from 2 to 4. In plants grown in a Mushroom house, 2 have been found, while plants from the field show 4. Whether the number 2 for cultivated forms is constant, or 4 for the field forms, has not been determined.

Development of Agaricus campestris. – The spores of the Mushroom in the field probably often germinate and produce new mycelium or “spawn,” though this is not necessary for the continuance of the plant from one year to another, since the spawn can live through the winter in the soil, and the following year then spreads. In ordinary Mushroom culture, however, the spores probably play little part in the propagation of the plant, since this is accomplished by the growth and propagation of spawn. If the soil where plants are growing is carefully dug away there will be seen slender and irregular whitish cords coursing through it, and some of them attached to the base of the stem. These whitish cords are what the horticulturist calls “spawn.” They are cords of mycelium, and are composed of numerous very slender and delicate whitish threads. This is the vegetative portion of the Mushroom. If the soil at the base of a tuft of young plants in a Mushroom bed be washed away, a large number of these cords will be exposed. This is the part of the plant, which grows and spreads through the soil, absorbing solutions of the organic matter in the soil for food.

Button Stage. – After an abundance of the mycelium, or spawn, is formed there appear here and there on the cords small rounded bodies formed by the upward growth of the threads of mycelium. These increase in size and grow toward the surface of the ground. Each one is the young stage, or button, of the Mushroom. As it enlarges, the upper end appears as a round body on a short stalk, thus outlining in the embryonic stage the different parts of the mature plant. The gills are forming on the under side of the cap. They are at this time covered. They appear on the under side of the minute constriction at the junction of the cap and stem. At this stage they are covered by a loose growth of mycelium extending from the upper part of the stem to the margin of the cap. This forms the veil. The gills are formed by mycelium growing downward on the under side of the cap in radiating rows, thus forming the lamellae. The plant now continues to enlarge and the cap expands. Just about maturity the veil ceases to grow and the expanding cap thus stretches it until finally the veil is ruptured, usually next the margin of the cap, and then it hangs as a collar or ring on the stem (seen at a, Fig. 1441.)

Position of Agaricus campestris in Classification. – One of the large subdivisions of the higher fungi is made up of the Mushrooms, toadstools, puff-balls, etc. All of these are characterized by a more or less well developed fruiting surface, or hymenium. The structural element of the hymenium is the basidium, and in the large number of the species the form of the basidium does not vary to any great extent from that of the common Mushroom. The basidium, then, is the characteristic fruit structure of this large subdivision of the fungi. For this reason, the plants included in this subdivision are termed the Basidiomycetes. The Basidiomycetes, taken in the sense of the earlier students of the fungi, were divided into two orders, according to the condition of the fruiting surface at the maturity of the plant, namely the Hymenomycetes and the Gasteromycetes. In the former, the fruiting surface is either exposed from the beginning, or if covered at first, is at last exposed before the maturity of the spores, just as the hymenium of Agaricus campestris, at first covered by the veil, is exposed before the maturity of the spores by the rupture of the veil. The Mushrooms, toadstools, etc., belong, therefore, to the Hymenomycetes. In the Gasteromycetes, on the other hand, the spores are matured before the hymenium is exposed, as in the puff-ball, earthstar, etc., which open after the spores are ripe.

Families of the Hymenomycetes. – The usage of the earlier botanists in the arrangement of families will be followed here, since there is not an opportunity to properly set forth the principles of classification adopted by some recent systematic works. The arrangement depends on the character of the fruiting surface or hymenium.

  • A. Fruiting surface uneven; i.e., in the form of plates, tubes or spinous processes.
    • 1. Agaricaceae, fruiting surface in the form of plates or gills.
    • 2. Polyporaceae, fruiting surface in the form of pores or tubes.
    • 3. Hydnaceae, fruiting surface in the form of spinous or tubercular processes.
  • AA. Fruiting surface even; i. e., not as in A, except in the case of plants of a gelatinous texture.
    • 4. Clavariaceae, plants more or less erect, standing out from the substratum, and covered on all sides by the hymenium.
    • 5. Thelephoraceae, plants either erect or diffused over the surface of the substratum, one side only (in the case of erect plants usually the under side) covered with the hymenium.
    • 6. Tremellineae, plants of a gelatinous texture, various in form.

AGARICACEAE. – The common Mushroom, Agaricus campestris, belongs to this family. The family Agaricaceae is made up of what are now popularly termed agarics. Very many of the species were once placed in the genus Agaricus. The genus became so large that it was subdivided into a large number of subgenera, many of which have recently been raised to the rank of genera. In thus subdividing the old genus Agaricus into a number of genera there has been a lack of uniformity on the part of systematists in the choice of a generic name for the common Mushroom. Saccardo retained the genus Agaricus for the common Mushroom and its near allies, although discarding the subgenus Psalliota. Some have employed the genus Agaricus, some Psalliota, others Pratella, and still others propose to restore the antiquated genus Fungus, and call our plant Fungus campestris. This is not the place for a discussion of the merits of any of these names, but it seems better in the present instance, at least, to use the generic name Agaricus with the limits of Psalliota Fries.

Other Species of the Genus Agaricus. – There are a number of other species of the genus, as thus limited, which, because of their size and esculent qualities, are worthy of mention.

Agaricus arvensis, the Horse Mushroom, grows in grassy fields and pastures during the autumn. It is a larger plant than the common Mushroom, has a thicker cap, longer stem, and the veil is double, the lower or outer portion splitting radially into a starshaped fashion and remaining attached to the inner portion. Agaricus silvicolus, the wood-inhabiting Mushroom, grows in woods. The whole plant is whitish, but tinged more or less with yellow, the cap is smooth, and the long stem has an abrupt and broad bulb. The veil is thin, membranaceous, but in some specimens shows a tendency to be double, as in Agaricus arvensis. Agaricus Rodmani grows along the streets of cities in the hard ground between the sidewalk and curbing, and similar places. It is entirely white, the cap thick and firm, the stem short, and with a short, thick, double annulus. Agaricus fabaceus (A. subrufescens, Peck) has a light reddish brown cap, a long stem somewhat enlarged below, and a ring which has soft scales on the under side formed, much as in A. silvicolus, from the cracking or splitting of the outer layer. The plant has the taste and odor of almonds. It grows in greenhouses. It sometimes grows in compost heaps. It often forms large clusters of many individuals. It has been successfully cultivated. Agaricus silvaticus grows in woods during late spring and summer. It is a large plant, usually about the size of the Horse Mushroom, but thinner, and with numerous minute dark scales on the surface of the cap, which form a solid patch of dark color at the center. In age, the cap is more or less flat, and it has been called the flat-cap Mushroom (A. placomyces). The stem is long, enlarged below, and the ring is double, exactly as in the Horse Mushroom. Agaricus comtulus, a small species, rather rare, but with a wide distribution, is regarded with suspicion by some.

COPRINUS. – In the genus Coprinus, 3 of the edible species are quite common. The spores are black and the gills and more or less of the cap dissolve at maturity into a black fluid.

Coprinus comatus, the Shaggy-mane Mushroom, or Horse-Tail, occurs in richly manured lawns or parks in early spring or late autumn. It is white in color, with a cylindrical cap 3-4 in. long and 1-2 in. in diameter. The cap is very shaggy, the scales often being black in color, while the gills are at first salmon color. The ring on the stem is free and movable. It is one of the best of the edible Mushrooms.

Coprinus atramentarius, the Ink-cap, grows in similar places. The cap is oval, from 1-3 in. long and nearly as wide. It is nearly smooth, and grayish in color. The ring is fixed and not at all prominent; best seen just as the margin of the cap is parting from the stem.

Coprinus micaceus, the glistening Coprinus, grows about old stumps and from old roots or other buried and rotten wood. It is smaller than the two species enumerated above, and tan in color, the cap when fresh being covered with thin, loose, flaky scales which glisten in the sunlight like mica particles, but they are easily rubbed off or washed off by rains.

LEPIOTA. – Of the white-spored agarics the genus Lepiota, with an annulus on the stem and the gills usually free from the stem, contains several edible species. Lepiota procera, the Parasol Mushroom, grows in pastures, lawns, and sometimes in gardens. Lepiota naucina, the smooth Lepiota, grows in similar places and is entirely white.

AMANITA. – The genus Amanita is closely related to Lepiota, and contains, besides several edible species, a number of poisonous ones, a few of which are the most deadly of all the Mushrooms. Amanita possesses the characters of Lepiota, with the additional character of a volva, or prominent universal veil, forming an outer layer of greater or lesser thickness and composition, which is ruptured as the cap expands and the stem elongates. In Lepiota the universal veil is not prominent, and it is further closely united with the surface of the cap. The volva in Amanita is often left as a prominent cup-like structure at the base of the stem (see Fig. 1443), and because it is present in some of the poisonous species is known popularly as the “poison cup,” “death cup,” etc. It is present, however, in some of the edible species.

Fig. 1443. The deadly Amanita. Amanita phalloides.

Amanita phalloides, the deadly Amanita (Fig. 1443), is one of the most fatal species. It is 4 to 6 in. high, and the cap is 2 to 4 in. in diameter. The cap is dark gray or umber, or whitish with a yellowish tinge, or quite yellow, or in some forms, especially European ones, the cap is green. In other cases the whole plant may be entirely white. The volva in typical forms splits at the apex as the young plant is expanding, and is left as a cup with prominent lobes, as shown in Fig. 1443. In other cases the volva is ruptured irregularly, so that portions of the universal veil are left on the surface of the cap. In still other cases the volva splits in a circumscissile fashion, that is, circularly or transversely about the middle, the lower half remaining attached to about the middle, the lower half remaining attached to the surface of the bulb at the base of the stem, while the upper half remain loosely attached to the upper surface of the cap, and is torn apart into scales as the cap expands. In these forms the volva forms a narrow rim or margin on the outer angle of the bulb, so that the latter appears saucer-shaped. The cap is rather slimy when moist. These great variations in this very poisonous species should make the novice very cautious regarding the species of Amanita, or indeed any species of Mushroom with which he is not quite familiar. This species of Amanita usually occurs in woods or groves or in the margins of woods, while the Agaricus campestris or the Lepiota naucina occur usually in open grassy places. But these differences of habitat cannot be relied on altogether, for the deadly Amanita, especially the white form, has been found in lawns far from woods, and in such cases might be mistaken for the smooth Lepiota, since this is white in color. The deadly Amanita is usually deeply seated in the ground, so that the stem might be broken in gathering it when the volva would be left in the ground, and it might easily be mistaken for some species of Lepiota.

Amanita verna, the Destroying Angel, is by some regarded as only a white variety of A. phalloides. The entire plant is white, the volva splits at the apex, and thus a prominent free limb of about three lobes remains at the base of the stem. The free limb remains more or less closely applied to the stem. The annulus is broad and entire, and hangs down as a broad collar from the upper part of the stem.

Amanita virosa is very near A. verna. It is distinguished only by the torn veil, portions of which remain clinging to the margin of the cap, and by the scaly character of the stem, characters which show every gradation into A. verna. Both are deadly poisonous.

Amanita muscaria, the Fly Agaric, is also a poisonous species, though not so dangerous as those named above, since the poisonous effect can be counteracted if treatment is promptly employed. The volva splits transversely into several concentric, interrupted rings which persist as scaly rings on the upper part of the bulb on the base of the stem, and as scattered scales on the surface of the cap. The cap is yellowish or orange-yellow, sometimes red in color, and in age sometimes fades out so that white forms appear. The gills are usually white, as are also the ring and the stem. Amanita Frostiana is a closely related species with the same color on the cap, but with yellowish gills and veil, though variations in the color are shown in different plants when the cap only may be yellow. The scales are usually yellow, but may also be white.

Of the edible species may be mentioned Amanita Caesarea, the “Royal Agaric” or Caesar’s Agaric.” The cap is bright orange or yellow, with prominent striae or furrows on the margin. The gills are orange, though the spores are white. The veil and stem are often yellow, especially in the larger specimens. The volva splits at the apex and is left at the base of the stem as a cup with a prominent free limb, which usually fits closely to the stem. The volva is white, and rarely are portions of it left on the surface of the cap. It is a very beautiful species, occurring during late summer and autumn in woods, and is more common in the southern states than north.

Amanita rubescens, another edible species, has a volva which is more or less friable, that is, it crumbles more or less into loose particles which easily wash off from the cap as well as from the base of the stem. The entire plant has a dull reddish tinge, and when bruised or cut quickly changes to a deeper reddish color due to a reddish juice in the plant. Small forms of the species do not show the color so well.

Amanita solitaria, the Solitary Amanita, is one of the largest species of the genus. It is almost pure white, the surface of the cap often being grayish, and sometimes with tints of brown in the scales, especially in old plants. It grows in rather open woods or by roadsides in woods. The volva is entirely broken up into mealy particles, which easily rub off, or there are conic scales, especially toward the center of the cap. The veil is very delicate and easily torn into shreds, which disappear soon. The stem has a large bulb, which tapers into a long, root-like process in the soil. The plant is said by some to be edible. Amanita strobiliformis is a closely related species, if it is not identical with it, and is said by some to be poisonous, so that caution should be employed in eating plants of this form unless one is certain of the species and of its edible qualities. A. strobiliformis is rarely found in this country and judging from the characters of certain plants attributed to it, there is a strong suspicion that it is only a form of A. solitaria with large scales.

Other native Mushrooms of economic importance may be mentioned:

Armillaria mellea, the Honey-colored Agaric, occurs in late summer and during the autumn about old stumps, and from roots. The plants are clustered, the cap is more or less covered with pointed blackish erect scales, the gills are attached to the stem, and an annulus is present. The plant is also a parasite, especially on the roots of coniferous trees, in some instances killing the trees. It develops under the bark long black cords of mycelium. The plant is edible.

Pleurotus contains several edible species: the oyster agaric, P. ostreatus; the elm Pleurotus, P. ulmarius; and the sapid Pleurotus, P. sapidus, all growing on tree trunks, stumps, etc., especially abundant in the autumn.

Tricholoma personatum, “blewits,” is regarded as an excellent edible species. It grows on the ground in woods. When young, the entire plant is of a pale lilac or violet color, the color fading out in age. The spores are of a light ochre color.

Cantharellus cibarius is the well-known chanterelle. It is yellowish in color, grows in woods on the ground, is somewhat irregular top-shaped, and the gills are mere folds, which run irregularly from the stem to the margin of the cap, and are much branched. It is one of the best edible species.

Marasmius oreades, the well-known Fairy Ring, or champignon, grows in lawns and pastures. It is white, with a cream-colored cap. It often grows in the form of rings on the ground, though not always.

The genus Lactarius contains a large number of species. The plants are more or less fleshy and are characterized by the presence of a milky juice contained in a system of tubes throughout the plant. This juice exudes in drops when the plant is bruised or cut. In the larger number of species the juice is white in color, in some it changes on exposure to the air to various shades of yellow, while in others the milk is orange, blue, etc., from the first. Lactarius deliciousus is one of the best of the edible species, as its name indicates. The milk is orange in color. The plant is dull orange in color and marked on the cap with concentric zones of darker color. In age bruises of the plant become more or less tinged with green. Lactarius volemus is dull orange in color, the color being uniform, the flesh quite firm, and the milk white, sweet and very abundant, quickly exuding in large drops or running from cut or cracked portions. Lactarius corrugis is closely related but darker in color, sometimes dark brown, the gills also being dark ochre-brown in color. Both species are excellent, and grow in the woods during summer and autumn. Lactarius piperatus is entirely white, with close and narrow white gills, and abundant milk which is very hot or peppery to the taste. It is said to be edible, but should not be confused with certain species having peppery milk, which are reputed to be poisonous. Lactarius resimus is another white species with white and very hot milk, which is suspected. Lactarius Indigo is of an indigo-blue color, with faint zones of a darker color on the cap, and with a dark indigo-blue juice.

The genus Russula is closely related to Lactarius, but lacks the milky juice. In this genus occur many of he brilliant-colored agarics. The entire plant is more or less brittle and easily breaks, the gills of many species crumbling easily when rubbed. Russula lepida, with reddish cap and stem, white gills with the red color from the cap extending a short distance on the ends of the gills, taste mild, is an edible species. Another edible species, Russula alutacea, has a reddish or purple cap, but the gills and spores are ochraceous in color. The taste is mild. Russula emitica is a poisonous species. The cap is rose-color or red, the cuticle easily peels off from the cap, the margin of the cap is deeply furrowed and warty along the ridges, the stem is white or reddish and the taste of the plant is peppery.

Of the tube-bearing Fungi (Polyporaceoe) the genus Boletus contains a number of edible as well as poisonous species. In shape the plants are like the Mushroom, but they have a porous surface instead of gills on the under side of the cap. Boletus edulis has a yellowish or dull brownish cap, pores white and closed at first, but yellowish or greenish yellow in age. Boletus felleus (poisonous) is of about the same size and resembles the edible species closely, but the tube surface is pink or flesh-color, and the taste is bitter. In the genus Polyporus most of the species grow on wood, trees, stumps, logs, branches, roots, etc. The sulfur polyporus, P. sulphureus, forms clusters of sulfur-yellow bracket-like caps, on various broad-leaved trees or stumps. Polyporus frondosus grows from roots at the base of dead oak stumps, forming large irregularly branched leafy masses with gray caps and whitish stems and pore surface. Both of these are edible.

In the spine-bearing Fungi (Hydnaceae) the under surface of the cap presents numerous spine-like processes. Hydnum repandum, in shape like a Mushroom, with the cap more or less irregular, and of a buff or cream color, is an excellent edible species. The Coral Hydnum, the Bear’s Head, the Medusa’s Head, and Hydnum erinaceum, all growing on trees, all white in color, and branched, or forming large masses from which long spines dangle, are all edible.

The Club Fungi (Clavariaceoe) are all said to be edible. The Horn of Plenty, Craterellus cornucopioides, funnel-shaped, and smoky in color, with a smooth under surface, belongs to the Thelephoraceoe, and is edible.

Among the Puff-balls (Lycoperdaceae) all the species when young and white inside are edible, that is, they are not poisonous. Some are better to the taste than others. The two best ones are the Giant Puff-ball, Lycoperdon giganteum and the Lycoperdon cyathiforme. Both of these grow in lawns or fields, the former grows sometimes to a large size, several feet in diameter; while the latter is 4 to 6 inches in diameter.

Fig. 1444. Morel – Morchella esculenta.

Besides the Mushrooms proper, which belong to the Basidiomycetas, certain of the large Ascomycetes are edible and are usually included in treatises on Mushrooms. In the Ascocomycetes the spores are borne on the inside of a club-shaped body called the ascus, and this is the chief point of difference in them from the Basidiomycetes. To the Ascomycetes belong the following. The Morels grow on the ground in damp places. They have a stout stem and a rounded or more or less elongated cap, which is deeply and coarsely pitted. Morchella esculenta, represented in Fig. 1444, shows well the general character of the genus. In Helvella, containing several edible species, the cap, is in the form of several (usually two) irregular flaps, sometimes free below from the stem, sometimes united with it. Lastly, the Truffles might be mentioned. They are subterranean Fungi rounded or globose in form, firm, and contain the spores inside of the rounded mass within sacs. Few have been found in this country, because they have not been diligently searched for. GEO. F. ATKINSON

Mushroom Culture.

There is no science of Mushroom culture. That is to say, one does not know why he fails. This is equivalent to saying that he does not know why he succeeds. By practice and experimenting he may become very skillful, but it is next to impossible for him to impart his knowledge. If he writes an article, he describes his method in detail and deprecates other methods; but the learner will be as likely to succeed by some other method, and neither man will know why. There are few people, if any, who succeed uniformly with Mushrooms. Beds made the same day and of the same material, planted from the same spawn, and similarly cared for, may give very different results. One bed may fail outright, and another may produce a good crop. Persons who make uniform commercial success of Mushroom-growing accomplish it by having many beds or by proceeding on a rather large base: it is infrequent that all the beds fail. The biological problems concerned in the propagation, growth and appropriation of food of the Mushroom must be understood before one can lay down principles for the culture of Mushrooms.

Decaying vegetable matter, a uniform and rather low temperature, a uniform supply of moisture, – these are the general requisites for Mushroom-growing. The decaying matter is supplied by horse manure. The manure is allowed to heat and is turned several times before it is placed in the bed. The heating itself is probably of no advantage except as it contributes to the decay of the material: heat can be supplied by other means if necessary. The broken and decaying manure is placed a few inches or a foot deep in beds. When the temperature is reduced to 90 degrees or less the spawn is planted. As soon as the bed has cooled sufficiently, it is covered with earth or litter to regulate the temperature and moisture.

The cultivated Mushroom is native in temperate climates. In the United States and Canada it grows naturally in fields and pasture. But it is grown indoors: this is because the conditions can be better controlled under cover, particularly the temperature. Now and then some one makes a success of growing Mushrooms out of doors, but this practice does not promise much for most parts of America. In parts of Europe, growing in the open is more successful. Cellars or pits are favorite places in which to grow Mushrooms. The conditions are uniform. Caves are favorite places in which to grow Mushrooms, because of the slight fluctuations of temperature and moisture. Cellars and caves are dark: thereby has arisen a belief that darkness is essential to the growing of Mushrooms, but this is an error. They often grow well in an unscreened greenhouse. Pastures are not dark. Spawn may be planted in a lawn, and Mushrooms will sometimes come; but it is seldom that the conditions are right for a crop.

Fig. 1445. A clump of young Mushrooms.

Mushrooms are in edible condition at any time from their first appearing above the ground to the time when the rim of the cap begins to turn up and the flesh to lose its softness. See Figs. 1440, 1441. For pickling, “buttons” are usually preferred; these are the young Mushrooms (Fig. 1445) taken before the cap has expanded.

Mushrooms are propagated by spores and spawn, usually the latter. Spawn is the mycelium. It may be dried, and will resume growth when congenial conditions are given. It will keep for a number of years in a cool, dry place. Dryness is essential. This spawn may be secured from any place in which Mushrooms are growing. The soil or manure containing the mycelium is broken into large lumps or flakes, and is planted in the desired place; the mycelium spreads through the bed and in time bears the fruiting stage or Mushroom. Formerly the spawn was gathered s needed, but since about 1830 it has been made or produced as a commercial product. For this purpose the spawn is grown in some prepared material, which may be dried and transported. The making of spawn is a business of itself. The English make and use the spawn mostly in brick-like masses of earth and manure (Fig. 1446.) The French use also a spawn borne in a loose litter-like material (Fig. 1446), although not all of the French spawn is made in France. The English or brick spawn comprises nine-tenths of the spawn used in America. The brick is made of a mixture in about equal parts of horse manure, cow manure and loam. These are wet and mixed until the material has the consistency of mortar. The material is then spread on a floor and is allowed to dry until it can be cut into pieces, or “bricks.” While the bricks are still moist, a hole the size of a walnut is made in the brick and fresh spawn is inserted. The bricks are then placed under cover or in a mild hotbed, where they are given such conditions as will cause the mycelium to penetrate them thoroughly. When the mycelium has ramified throughout the mass, and the surface has a cloudy look, the brick is dried and stored. This brick may be likened to a yeast cake.

Fig. 1446. Mushroom spawn. English spawn, or “bricks,”on the left; French or “flake” spawn on the right.

Expert Mushroom-growers believe that spawn, which is made over and over again from the mycelium tends to become weak and to produce small crops of thin-fleshed Mushrooms. They believe that the spawn now and then should be inoculated afresh from the spores. Spawn made directly from the spores is known as “virgin spawn.” It is made by incorporating the abundant spores of ripe Mushrooms with the material of which spawn is made. It is probable that many of the large, thick Mushrooms, which come up in odd places in the greenhouse arise from spores.

Mushrooms have been known as edible products from very early times. Pliny mentions them, but his writings are mostly warnings not to eat them because they are poisonous. He places them “among those vegetable productions which are eaten with risk.” The following are some of his remarks respecting the Mushroom:

“The generative principle of the Mushroom is in the slime and the fermenting juices of the damp earth, or of the roots of most of the glandiferous trees. It appears at first in the shape of a sort of viscous foam, and then assumes a more substantial but membranous form, after which, as already stated, the young Mushroom appears. In general, these plants are of a pernicious nature, and the use of them should be altogether rejected; for if by chance they should happen to grow near a hobnail, piece of rusty iron, or a bit of rotten cloth, they will immediately imbibe all these foreign emanations and flavours, and transform them into poison. Who, in fact, is able to distinguish them, except those who dwell in the country, or the persons that are in the habit of gathering them? There are other circumstances, too, which render them noxious; if they grow near the hole of a serpent, for instance, or if they should happen to have been breathed upon by one when just beginning to open; being all the more disposed to imbibe the venom from their natural affinity to poisonous substances. It will therefore be as well to be on our guard during the season at which the serpents have not as yet retired to their holes for the winter. The best sign to know this by is a multitude of herbs, of trees, and of shrubs, which remain green from the time that these reptiles leave their holes till their return; indeed, the ash alone will be quite sufficient for the purpose, the leaves of it never coming out after the serpents have made their appearance, or beginning to fall before they have retired to their appearance, or beginning to fall before they have retired to their holes. The entire existence of the Mushroom, from its birth to its death, is never more than seven days.”

Two hundred years and more ago Mushrooms were cultivated. The following directions, given by Philip Miller in 1754, are very like methods which are sometimes advised today, with the exception of the method of securing the spawn:

“In order to cultivate them, if you have no Beds of your own, or neighboring Gardens, which produce them, you should look abroad in rich Pastures, during the Months of August and September, until you find them (that being the Season when they are produced); then you should open the Ground about the Roots of the Mushrooms, where you will find the Earth, very often, full of small white Knobs, which are the Off-sets, or young Mushrooms: these should be carefully gathered, preserving them in Lumps with the Earth about them: but as this Spawn cannot be found in the Pasture, except at the season when the mushrooms are naturally produced, you may probably find some in old Dunghills, especially where there has been much Litter amongst it, and the Wet hath not penetrated it to rot it; as likewise, by searching old Hot-beds, it may be often found: for this Spawn hath the Appearance of a white Mould, shooting out in long Strings, by which it may be easily known, wherever it is met with; or this may be procured by mixing some long Dung from the Stable, which has not been thrown on an Heap to ferment; which being mixed with strong Earth, and put under Cover to prevent Wet getting to it, the more the Air is excluded from it, the sooner the Spawn will appear: but this must not be laid so close together, as to heat; for that will destroy the Spawn: in about two Months after, the Spawn will appear, especially if the Heap is closely covered with old Thatch, or such Litter as hath lain long abroad, so as not to ferment: then the Beds may be prepared to receive the Spawn: these Beds should be made of Dung, in which there is good Store of Litter; but this should not be thrown on an Heap to ferment: that Dung which has lain spread abroad for a Month or longer is best: these Beds should be made on dry Ground, and the Dung laid upon the Surface : the Width of these Beds at Bottom should be about two Feet and an half, the Length in proportion to the Quantity of Mushrooms desired: then lay the Dung about a Foot thick, covering it about four Inches with strong Earth; upon this lay more Dung, about ten Inches thick: then another layer of Earth; still drawing in the Sides of the Bed, so as to form it like the Ridge of an House; which may be done by three Layers of Dung, and as many of Earth. When the Bed is finished, it should be covered with Litter, or old Thatch, to keep out Wet, as also to prevent its drying: in this situation it may remain eight or ten Days; by which time the Bed will be in a proper Temperature of Warmth to receive the Spawn; for there should be only a moderate Warmth in it, great Heat destroying the Spawn, as will also Wet; therefore when the Spawn is found, it should always be kept dry until it is used; for the drier it is, the better it will take in the bed: for I had a Parcel of this Spawn, which had lain near the Oven of a Stove upward of four Months, and was become so dry, as that I despaired of its Success: but I never have yet seen any which produced so soon, nor in so great Quantity, as this.

“The bed being in proper Temperature for the Spawn, the Covering of Litter should be taken off, and the Sides of the Bed smoothed; then a Covering of light rich Earth, about an Inch thick, should be laid all over the Bed; but this should not be wet: upon this the Spawn should be thrust, laying the Lumps two or three inches asunder: then gently cover this with the same light Earth, above half an inch thick; and put the Covering of Litter over the Bed, laying it so thick as to keep out Wet, and prevent the Bed from drying: when these Beds are made in the Spring or Autumn, as the Weather is in those Seasons temperate, so the Spawn will then take much sooner, and the Mushrooms will appear perhaps in a Month after making: but those Beds which are made in Summer, when the Season is hot, or in Winter, when the Weather is cold, are much longer before they produce.

“The great Skill in managing of these Beds is, that of keeping them in a proper Temperature of Moisture, never suffering them to receive too much Wet: during the Summer season, the Beds may be uncovered to receive gentle Showers of Rain at proper times; and in long dry Seasons the Beds should be now-and-then gently watered; but by no means suffer much Wet to come to them: during the winter season they must be kept as dry as possible; an so closely covered, as to keep out cold: in frosty or very cold Weather, if some warm Litter, shaken out of a Dung-heap, is laid on, it will promote the Growth of the Mushrooms: but his must not be laid next to the Bed; but a Covering of dry Litter between the Bed and this warm Litter: and as often as the Litter is found to decay, it should be renewed with fresh: and as the Cold increases, the Covering should be laid so much thicker. If these Things are observed, there may be plenty of mushrooms obtained all the Year: and these produced in Beds are much better for the Table than any of those which are gathered in the Fields.”

Probably the first book in English to be devoted exclusively to the Mushroom was written in 1779 by John Abercrombie, London, and published under the title of “The Garden Mushroom: Its Nature and Cultivation. A Treatise, exhibiting Full and plain Directions, for producing this desirable Plant in Perfection and Plenty, according to the true successful Practice of the London Gardeners.” Aside from the manner of securing the spawn, the advice given by Abercrombie would apply very well at the present day. He says that the spawn may be obtained from the dung of horse stables, from hotbeds, composts, cucumber and melon beds, old Mushroom beds, livery stable yards, horse mill-tracks, old dung-heaps where “some straggling Mushrooms are seen to rise naturally in the autumn,” in kitchen-gardens in which Mushrooms have been seen, and in old pastures and meadows. The best season to find the spawn is in the autumn and the early part of winter. The frequent occurrence of Mushrooms in the covered mill-tracks, where horses worked on tram-cars and on power machinery, led to the use of the thoroughly tramped manure as spawn. This spawn gave very excellent results, probably because it was partially seeded from the spores of the Mushrooms which ripened there and were tramped into it. It is probable that this mill-track spawn gave rise to the idea of the Mushroom brick, which is now the chief means – at least, in England and America – of growing Mushrooms. The name “mill-track” is still used as a trade name for Mushroom spawn, although very little, if any, of it really comes from mill-tracks.

In America there is only one book devoted wholly to the growing of Mushrooms. This is by William Falconer and known as “Mushrooms: How to Grow Them” (1891). L.H. Bailey

For Mushrooms, a supply of fresh horse manure should be procured, if possible each morning, that from grain-fed carriage horses being the most desirable. The strawy portion we discard. The manure is thrown in a heap on the floor of an open shed, and is turned over each morning for a few days. Before the heat of the manure has subsided sufficiently to permit the bed being made, mix about one-third as much loam screened through a ¾-inch sieve as there is of manure. We have had better success with loam mixed with the manure than when it was not used. The rank heat having escaped from the heap, it can at once be made into a bed, a depth of from 9 to 12 inches being about right. The manure is placed in layers and pounded as hard as possible with a wooden mallet or brick; it can be well trodden where treading is possible. We spawn when the temperature of the bed has subsided to 90 degrees. It is a little unsafe to spawn at a higher temperature, and if left until the heat drops below 80 degrees, Mushrooms will be much more tardy in appearing and of poorer quality. English Milltrack spawn usually gives the best results. The spawn is broken into pieces as large as a walnut and inserted 2 or 3 inches deep, some 4 to 5 in. apart each way, pressing the surface firm after the insertion. Ten days later 2 inches of good loam is spread over the surface and pounded in hard. The beds are then covered with meadow hay or straw, and, given proper atmospheric conditions, should require no further attention until after Mushrooms have appeared, which may be in four weeks or not until four months later. The time when the first buttons will appear is very uncertain. It does not do to be of a highly strung nervous temperament in Mushroom culture. We have spawned beds and despaired of success, when we have been gratified by getting a firstclass crop thirteen to sixteen weeks after spawning.

A dry atmosphere is inimical to the well-being of Mushrooms, and success is uncertain where such conditions exist. It is generally conceded that watering the beds often does more harm than good, but it must be remembered that the fact of the bed becoming dry only retards the production of the crop, and does not lessen the chance of Mushrooms appearing once the bed has become sufficiently moist. If the beds are made very compact there is less probability of them drying out and less likelihood of their injury by any sudden excess of either drought or moisture. When water has to be given we prefer to use it of a temperature of 85 to 90 degrees and to water only the dry portions of the bed, which are wetted as evenly as possible. When the first crop is exhausted and the bed has become somewhat dry, we use warm water and add a little nitrate of soda to it, covering the surface with hay after watering. This usually induces a good second crop to come.

We start to collect manure for the beds early in September, and continue to do so until early November. Usually the beds are made under the benches of some of the houses, where a temperature of 55 to 60 degrees can be maintained, but any cellars or cave where such a temperature can be kept up are even better than greenhouses for Mushroom culture. The beds are always kept as dark as possible. Cockroaches, wood-lice and other pests must be poisoned or trapped, else they soon ruin a crop. W.N. CRAIG

Mushroom-growing is interesting work, and it is the uncertainty that is the cause of it. Most Mushroom growers are in doubt when spawning their beds as to whether mushrooms will appear, or the work be a failure. The writer has had excellent success with Mushroom culture and remarkable failures. Failures in a Mushroom crop are not easy to explain. The fault may be in making up the bed, or it may be in the spawn. A few years ago a bed was spawned with three lots of spawn; two beds were a success, while the other was a complete failure, – a proof that the bed is not always the cause of failure. Mushrooms may be gown successfully under the greenhouse benches, providing the drip can be kept off the beds; also in cellars; but the preference is for a Mushroom house built for that purpose. The house of which the writer has charge is built into a bank in such a position as to require very little fire heat to keep up the temperature. Of course air-spaces must be provided in the walls, according to the size of the house.

Two methods of making the beds may be described: (1) Collect fresh horse manure until there is enough to make a bed. The manure should be kept where it can be protected from rains, an open shed preferred. Turn the manure every other morning for a week, or until danger of burning is over. In making the beds, from 9 in. to a foot of manure is used. Beds should be thoroughly firmed, putting in a layer of manure, then firming, then another layer, until the desired depth is secured. Assuming that the bed goes up after making to 100 or 110 degrees, then gradually drops, it is safe to spawn at 90 degrees. Spawn should be inserted in the manure say 2 or 3 in. deep, and about 5 in apart. In a week or ten days after spawning, cover with 2 in. of good loam. Good loam from the pasture, soil from the garden, and also old rose soil have been used with good results. It is customary to mix a little soil through the manure before making the bed. After the soil is on the bed and firmed down, a covering of straw will be beneficial, as it prevents the beds from drying out. Should they dry out, water must be applied, which should be at a temperature of 75 or 80 degrees. Mushrooms should be gathered from six to eight weeks after making the bed. Keep the house at a temperature of 55 to 60 degrees. (2) The second method, which seems to be the better, is for every load of fresh horse manure to add a load of old thoroughly rotted manure, or a load of old Mushroom manure. The aim is to get enough old manure to prevent the other from burning. The two are mixed, and the following day the bed is made. This method does away with a great amount of labor turning the manure; the bed also has a tendency to hold the moisture a greater length of time. The details of making the bed are the same as in the other method. This is a simple way to make the beds, but the results will follow with as much certainty as with any other method. WILLIAM TURNER

The writer’s first trial with Mushrooms was made in a soap box under a bed, and the Mushrooms did well. That was 45 years ago. The next year he went into the business on a larger scale, growing them in the cellar, and a good crop was the result. He received $1.50 a pound, or $220 for the lot. A cellar under the parlor was devoted to the crop, and $350 worth was sold. Then a place was built under the ground with good ventilation, but it was not a success. The drip was too much. A cellar under the carriage house, which had no drip, made a good place, leading to the belief that a place with a Mushroom house under a building is the best place in which to grow them. They need a dry place. If we have a dry summer and light rains in September, or heavy dews, we will pick plenty of Mushrooms in the fall outdoors. In growing Mushrooms, we must imitate nature. The money that is wasted for spawn alone in one year would make a fortune for some persons. People get wild to grow Mushrooms. Some secure a crop, but others get nothing. The young man must try a little at a time. He should learn from the experiences of different men. A man can make money in this business, and he can lose it. The writer has had failure and success, but he now grows two tons every year.

Mushroom spawn runs best in anything that is dry. It is difficult to find out what moisture is wanted, and to get the material in the right state. The writer prefers to secure his manure on the cars fresh from the stable. Turn it over eight or nine times, once every day, so it will not burn, and put in dirt. To twenty tons add five cart-loads of earth. This earth is secured from sod from the hedges around the farm, taken the first of June and piled up to rot, so it will be ready for mixing in the manure. When the manure is in the right state, put it in beds 8 inches deep. The beds (made in houses) are made up like bunks on a ship and are 100 feet long, 4 feet wide and 3 feet between the beds to allow a man to go through with a wheelbarrow. One house is 20 feet wide. It contains 13 beds 100 feet long. It is heated by hot water and the temperature is kept at 60 degrees. There are three large houses, and all of them with greenhouses on top, where lettuce, cauliflower, parsley, rhubarb and radishes are grown with the same heat that grows the Mushrooms. English spawn is used. It should be fresh and new. The spawn is placed 6 inches apart in the beds, in pieces the size of a black walnut. When the heat goes down to 90 degrees the spawn is put in, and in six weeks the Mushrooms are ready for picking. The beds last from three to four months. The Mushrooms are packed in boxes and shipped to New York. S.W. WORTMAN

The Trade in Mushrooms. – The trade in Mushrooms has grown from a supply of 30 to 50 pounds a day to the enormous quantity of one-half to three-quarters of a ton. In fact, the trade has increased in proportion with the price, according to demand and supply. The best season for the consumption of Mushrooms is the late fall and winter months, as they keep in the cool, dry weather for several days, and small dealers have no trouble with them spoiling on their hands. The price during these months varies according to supply and demand. In the summer months a few will do well, but they spoil so readily in the heat that dealers do not care to handle any stock; therefore, if there were a large supply from June until October they would surely go to waste. The growers generally take advantage of this and renew their beds in summer, and prepare for the coming season. One great mistake is that the small grower is too anxious to reach the consumer. He wants to save the little which the middleman or distributor gets, and he gives them to the retailer, to restaurants, or to others, and these persons often take advantage of him. He is sometimes compelled to take from 25 to 50 percent less than market price, and he injures the market as well. All classes now buy Mushrooms. If the supply is scarce and price high, they go only to the better class of hotels and restaurants; but as the price gradually decreases the consumption increases and the poorer grade of hotels and restaurants and families consume them. The consumption of canned and dried Mushrooms is not increasing as rapidly as that of the fresh-grown, and we are led to believe that in the near future our home-grown Mushrooms will be canned and dried as the foreign are; in fact, some of the canners are now making ketchup of the seconds and poorer grades. We believe that the consumption can be doubled and possibly trebled at a good profit if sold at half the present prices. We expect to hear before long of some house that will make a specialty of Mushrooms and sell nothing else. ARCHDEACON & CO.