The Project Gutenberg EBook of Mushroom Culture, by W. Robinson This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org Title: Mushroom Culture Its Extension and Improvement Author: W. Robinson Release Date: October 6, 2012 [EBook #40952] Language: English Character set encoding: UTF-8 *** START OF THIS PROJECT GUTENBERG EBOOK MUSHROOM CULTURE *** Produced by Peter Vachuska, Rosanna Murphy, Dave Morgan and the Online Distributed Proofreading Team at http://www.pgdp.net Transcriber’s Notes: Punctuation has been standardised. Spelling has been retained as it appears in the original publication except as marked like this in the text. The original text appears when hovering the cursor over the marked text. A list of amendments is at the end of the text. Cover. The Country Series OF FARM, GARDEN, AND RURAL BOOKS FOR GENERAL USE, PUBLISHED UNDER THE DIRECTION OF W. ROBINSON, F.L.S., Founder of “The Garden,” “Farm and Home,” and “Gardening Illustrated;” Horticultural Editor of “The Field;” Author of “The Parks and Gardens of Paris,” “Alpine Flowers for English Gardens,” “The Wild Garden,” “Hardy Flowers,” &c. MUSHROOM CULTURE ITS EXTENSION AND IMPROVEMENT MOUTH OF MUSHROOM-CAVE NEAR PARIS BOTTOM OF SHAFT OF MUSHROOM-CAVE MUSHROOM CULTURE ITS EXTENSION AND IMPROVEMENT BY W. ROBINSON, F.L.S. AUTHOR OF “The Parks and Gardens of Paris,” “Alpine Flowers,” &c. WITH NUMEROUS ILLUSTRATIONS NEW YORK GEORGE ROUTLEDGE AND SONS NO. 9 LAFAYETTE PLACE LONDON, GLASGOW AND MANCHESTER PREFACE. My reasons for writing this book are: First, that Mushroom Culture is but little practised in this country compared to the extent to which it ought to be, considering the abundance of the necessary materials in all parts of these islands, both in town and country, and the high estimation in which the Mushroom is held. I now refer to ordinary Mushroom Culture as practised in our best private gardens. I believe it possible and desirable to extend this, the only phase of the Culture that can be called popular, in a tenfold degree, and that every place in which a gardener and horses are kept should be abundantly supplied with Mushrooms throughout the greater part of the year. Secondly, that although Mushroom Culture as usually practised is perfectly well known to good cultivators, a simpler and fuller account of it than has yet appeared in any English book on the subject is desirable for the unpractised amateur and cultivator. Thirdly, that Mushroom Culture is at present confined to a too narrow groove; and a belief that the general gardening public should have a broad and clear idea of the several ways in which they may procure abundance of excellent Mushrooms with very trifling expense. Even many of the best private growers never think of it except as illustrated on their comparatively small beds in small houses. I believe that if the knowledge of how easily and in how many ways they may be grown, apart from the usual mode, were sufficiently spread, it would lead to the production of many times our present supply. Fourthly, a desire to introduce to this and other countries the system of Mushroom Culture on a very large scale carried on in caverns beneath the environs of Paris, which caverns I visited in 1868. To these reasons I might add a wish to call attention to the waste of money for Mushroom-spawn that now occurs in nearly every garden. There is not the slightest necessity for this. In every garden where Mushrooms are grown abundance of spawn may be made. Mr. W. P. Ayres writes lately to tell me that in a great midland garden where the spawn bill used to amount to 18l. or 19l. a year, by saving the spawn as the Parisian growers do, all expense for this article is abolished. I do not attempt to praise or even duly weigh the merits of the Mushroom—that could only be adequately done by the immortal Brillat-Savarin. He, however, seems to have somewhat neglected this most precious of légumes. None but his serious soul could have approached the subject with the necessary solemnity. Nobody but he who first saw the deep dangers of hurried, thoughtless, and irreverent feeding, could have done justice to its exquisite flavour when in the best condition, or could have explained how deliciously it combined the virtues of herb and flesh, unspeakably superior to either. Let us, in passing, quote one of his aphorisms, contributed to form the base éternelle à la science: “La découverte d’un mets nouveau fait plus pour le bonheur du genre humain que la découverte d’une étoile!” Now, I do not hesitate to say that the introduction of the Mushroom into our domestic economy in as great a degree as we have it in our power to produce it, would practically be the addition of a new agent in our cuisine, second to none for its delicacy, and unsurpassed for utility. It is true the Mushroom is plentiful in its season, but it is with us, at all seasons when it is not to be gathered in the open air, a luxury to numbers of owners of gardens who have means to grow it. As for the much larger class who ought to be supplied from our markets, they seldom see or taste a Mushroom except when these occur in profusion in our fields, though every cart of stable-manure produced in this great horse-keeping country may, on its way towards decomposition and replenishing the earth, be made a nidus for furnishing many dishes of them. The illustrations showing the cave-culture of mushrooms are from my “Parks, Promenades, and Gardens of Paris.” And the frontispiece is after two large cuts of the mushroom caves of Paris, which appeared in the Illustrated London News some time after the appearance of my work. The illustrations of edible fungi are by Mr. Worthington G. [v] [vi] [vii] [viii] Smith, who knows and draws these interesting subjects so thoroughly well; and the other figures are by Mr. Hodgkin. CONTENTS. PAGE WHERE MUSHROOMS MAY BE GROWN 1 CHAPTER I. MUSHROOM CULTURE IN THE MUSHROOM-HOUSE 2 CHAPTER II. THE PREPARATION OF THE MATERIALS, ETC. 13 CHAPTER III. MUSHROOM-SPAWN 23 CHAPTER IV. SPAWNING AND AFTER-TREATMENT 33 CHAPTER V. CULTURE IN SHEDS, CELLARS, ARCHES, OUTHOUSES, AND ALL ENCLOSED STRUCTURES OTHER THAN THE MUSHROOM-HOUSE 43 CHAPTER VI. THE CAVE CULTURE OF MUSHROOMS, NEAR PARIS 57 CHAPTER VII. CULTURE ON PREPARED BEDS IN THE OPEN AIR IN GARDENS AND FIELDS 77 CHAPTER VIII. CULTURE IN GARDENS, ETC., WITH OTHER CROPS IN THE OPEN AIR 84 CHAPTER IX. MUSHROOM CULTURE IN PASTURES, ETC. 88 CHAPTER X. THE COMMON MUSHROOMS 95 CHAPTER XI. MODES OF COOKING THE COMMON MUSHROOMS 102 CHAPTER XII. SOME OF THE MOST COMMON AND USEFUL EDIBLE FUNGI 108 [ix] [x] [1] MUSHROOM CULTURE. WHERE MUSHROOMS MAY BE GROWN. The places in which mushrooms can be grown may be roughly grouped as follows:—1. In the mushroom-house proper. 2. In sheds, cellars, out-houses, stables, railway-arches, &c. 3. In deep caves, like those near Paris, described further on. 4. In the open air, in gardens or fields, on prepared beds. 5. In gardens, among various crops, without any preparation beyond inserting the spawn. 6. In pastures where the mushroom is not already established. To these I might add another group, illustrated by the case of a Belgian cook who grew a dish of mushrooms in a pair of old wooden shoes; but practically we can treat of nearly every possible mode of growing the mushroom under the above headings. CHAPTER I. MUSHROOM CULTURE IN THE MUSHROOM-HOUSE. Fig. 1. Mushroom-house at back of hothouses. Culture in the mushroom-house being the most practised, and, on the whole, the most important phase of the subject, we will first treat of it. And first of the mushroom-house itself. Its construction is very simple: the conditions to be obtained are equable temperature, secured by thick or hollow walls and by a double roof. Figure 1 shows a house designed for me by Mr. Ormson, the well-known horticultural builder. It is situated at the back of the hothouses, where a flow and return pipe can be run through for artificial heat. The shelves for making the beds upon are of slate 1½ in. thick, or of stone 2½ in. thick, built into the walls, and into brick piers built in cement. Upright slates, to slide in grooves, are placed along the front of the shelves to keep the beds in. [2] [3] Fig. 2. Ground-plan of preceding. The floor may be of paving tiles, or bricks, laid on concrete: a skylight or two may be fixed in the roof, for the purpose of admitting a little light, and air when necessary. The engraving (fig. 2), shows a house of this description, 12 feet wide by 20 feet long, inside measure, but, of course, the length may be extended as circumstances may require. As it is of importance in mushroom-growing that the air of the house should be kept moderately moist, the underside of a slate or tile roof should be lathed and plastered. Fig. 3. View of unheated mushroom-house. Fig. 4. Section of preceding figure. Figure 3 represents a mushroom-house suitable for people of small means, or those who cannot adopt plan No. 1. It is designed with a view to growing mushrooms during the greater part of the year, without the aid of artificial heat. To this end it is constructed in such a way as not to be affected by changes of the external temperature, as will be seen by the engraving. The walls are hollow, and banked round with the soil excavated from the interior. The roof is thatched with reeds, and the ends stud-work, lined inside with boards, and outside with split larch poles: the cavity to be filled with sawdust or cut straw; a small diamond-shaped ventilator, hung on pivots, to be fixed in each end. The floor may be of concrete, or burnt clay well rammed; and the beds are retained in their place by boards nailed to good oak posts. Care should be taken to put in efficient drains, so that no stagnant damp may exist about the building. [4] [5] Fig. 5. Section of mushroom-house at Frogmore. Though the preceding cuts show how we may best attain our object, a few more illustrations of mushroom-houses are desirable here. Figures 5 and 6 exhibit the plan of the mushroom-houses at Frogmore, obligingly communicated by Mr. Rose. Fig. 6. Ground-plan of mushroom-house at Frogmore. It need hardly be said that in such large mushroom-houses rhubarb and sea-kale may be easily forced, and barbe de capucin, endive, &c. blanched. A small hot-water apparatus, with a 3-inch flow and return pipe, affords the best means of heating a mushroom- house which is not so situated that it may be heated from the boilers of adjacent hothouses. The best position for the mushroom-house is against a north wall. The usual precautions for guarding against damp walls and floor should be adopted in the case of the mushroom-house, and the walls should be hollow. Forsyth’s mushroom-house is described by the designer in Loudon’s Gardener’s Magazine. Fig. 7 is a transverse section, showing the arches under and over the beds, the thoroughfare a is the middle, and the position of the hot-water pipes, c; b is an open shed and general workshop, the receptacle of everything requiring protection, and too clumsy to be otherwise housed. Fig. 7. Mushroom-house under shed. [6] [7] A shed of this description is an indispensable adjunct to every well-ordered garden, and in the present case it serves as a roof to the mushroom-house. In the centre of each vault, shown in fig. 7, a circular ventilator, d, 9 in. in diameter, should be made, having a stone and cast-iron stopper, with a folding ring. The whole roof of the mushroom- house is covered over with pavement, which at the same time forms the floor of the shed above. Mr. Forsyth objects to cast-iron shelves “on account of the rust, and to slate shelves, as being cold and damp, and therefore not suitable to the purpose;” but he knows of no objection to shelves built of bricks and mortar, kerbed with hewn stone 3 in. wide, and clamped together with lead. Fig. 8. Mushroom-house at Stoke Place. Fig. 9. The annexed diagrams (figs. 8 and 9) exhibit the mushroom-houses used at Stoke Place, both for summer and winter use, as described by Macintosh in the “Book of the Garden.” “Of course the former is not heated; the latter is, by 4-inch hot-water pipes, which are brought from a boiler constructed to heat at the same time a range of pits for pines, melons, &c., 89 feet long and 7 feet wide. The shelves are close-bottomed to prevent the beds from drying too rapidly, and to require less watering, which Mr. Patrick thinks a very important precaution in mushroom culture. Ventilation is effected by a slide in the door, and a wooden trunk up through the arch and roof, with a slide in it also. We do not exactly see the motive of Mr. Patrick, whom we have long known and esteemed as one of the best gardeners in England, in adopting the span roof over this house, as, from its situation behind the garden wall, a lean-to roof would have been cheaper and carried off the rain-water better. It is rather a novel, but still a good plan, to have the inner roof constructed of a brick arch, as it will of course save the outer one from decay, to which all mushroom- house roofs are liable more than any other kind of garden building. This house struck us at first sight as very complete, excepting in breadth. We should increase it to 9 feet—that is, 3 feet for the breadth of the beds on each side, and the same for the footpath, which at present is inconveniently narrow.” [8] [9] Fig. 10. Russian mushroom-house. The Russian mushroom-house (fig. 10) is thus described by Mr. Oldacre, in the Horticultural Society’s Transactions, vol. ii. first series. “The outside walls should be 8½ feet high for four heights of beds, and 6½ for three heights, and 10 feet wide inside the walls. This is the most convenient width, as it admits of shelves 3½ feet wide on each side, and affords a space through the middle of the house 3 feet wide, for a double flue and a walk upon it.” Hot- water pipes were not in use when this house was erected. “The walls should be 9 inches thick, and the length of the house as may be judged necessary. When the outside of the house is built, place a ceiling over it (as high as the top of the walls) of boards 1 inch thick, and plaster it on the upper side with road sand well wrought together, 1 inch thick, (this will be found superior to lime), leaving square trunks, f, in the ceiling 9 inches in width, up the middle of the house, at 6 feet distance from each other, with slides, s, under them, to admit and take off air when necessary. This being done, erect two single-brick walls, v v, each five bricks high, at the distance of 3½ feet from the outside walls, to hold up the sides of the lower beds, a a, and form one side of the air-flue, t u t u, leaving 3 feet up the middle, t x t, of the house for the floor. Upon these walls, v v, lay planks, t u, 4½ inches wide and 3 inches thick, in which to mortise the standards, t k, which support the shelves. These standards should be 3½ inches square, and placed 4 feet 6 inches asunder, and fastened at the top to the ceiling joists. When the standards are set up, fix the cross-bearers, i n i n, that are to support the shelves, o o, mortising one end of each into the standards, n, the other into the walls, i. The first set of bearers should be 2 feet from the floor, and each succeeding set 2 feet from that below it. Having thus fixed the uprights, t k, and bearers, i n, at such a height as the building will admit, proceed to form the shelves, o o, with boards 1½ inches thick, observing to place a board, d d, 8 inches broad and 1 inch thick, in the front of each shelf, to support the front of the beds. Fasten this board on the outside standards, that the width of the beds may not be diminished. The shelves being completed, the next thing to be done is the construction of the flue (p in section), which should commence at the end of the house next to the door, run parallel to the shelves all the length of the house, and return back to the fireplace, where the chimney should be built; the sides of the flue inside to be of the height of four bricks laid flatways, and 6 inches wide, which will make the width of the flues 15 inches from outside to outside, and leave a cavity, t u, on each side betwixt the flue and the walls that are under the shelves, and one, x y, up the middle, betwixt the flues, 2 inches wide, to admit the heat into the house from the sides of the flues.” The introduction of this form of house by Mr. Oldacre has led to much improvement in our mushroom culture. The first house of this kind erected in England, was built at Shipley, near Derby, in the garden of E. M. Mundy, Esq., by the father of Mr. W. P. Ayres, whose name will be found frequently mentioned in this work. There brick arches were formed for the shelves, and though built more than half a century ago, the house is still in good condition. Although slate is generally used for the shelves, the adoption of cast-iron gratings for this purpose is well worth a trial, as by this means we may be enabled to cut mushrooms from the under as well as the upper side of the bed. CHAPTER II [10] [11] [12] [13] THE PREPARATION OF THE MATERIALS, ETC. Before we deal with the various ways of growing the mushroom, we will speak of the preparation of the material. As stable manure not only furnishes the nutriment, but forms the very soil in which mushrooms are produced artificially, and also supplies the heat which enables us to grow them to perfection at all seasons, by far the most important point connected with their culture is the management of this. It is very simple, but frequently, even by excellent gardeners, considered to require much more trouble and nicety than is really necessary. For example, it is quite common in good gardens to see the droppings collected carefully in some shed, or in the mushroom-house, and turned over almost as tenderly and carefully as the contents of the fruit-room. Good mushrooms are well worth this trouble; but, as it is quite unnecessary, it should not be done except in special cases. To show the diversity of opinion among excellent mushroom-growers as to the preparation of the manure, I will quote a few of our most trustworthy authorities on the subject. Mr. W. Early, in “How to Grow Mushrooms,” lays great stress on the importance of gathering the droppings in a dry state. “Every advantage should be taken of opportunities of securing and placing them in any open shed, or other similar position, where they can be effectually sheltered from rains. In such a place, whilst the process of collecting is going on, every portion should be spread loosely over the floor, in moderate sized ridges, or in any other manner that will allow the air to get amongst it to assist in drying. It should also be tossed over or turned, and lightened up daily for the same purpose, until a sufficiency is gathered together for immediate use.” This may be taken as a sample of the practice very extensively followed in this country. Happily, we have excellent mushroom growers who succeed without all this trouble, as the following remarks of Mr. J. Barnes will show: —“For the last thirty years I have made my beds entirely on the floor in sheds, wheeling in the stable dung as it is brought fresh from the stable, adding a fourth, or a little more than a fourth, of good friable loam, mixing both well together, pressing firmly down, and letting it remain about a week or so untouched. At the end of that time we turn it over, and if we consider it in too strong a state of fermentation we add a little more soil, and then tread down firmly. Very soon the bed is ready to be spawned, and encased in a couple of inches of soil; and in this way we get the finest crops of mushrooms, the beds remaining a long time in bearing. After the beds have been some time, say from six to twelve weeks, in bearing, and begin to get dry, and cease to bear well, we water them thoroughly with very clear liquid manure, made from sheep or deer or cow manure, which seems to start them again into bearing, and then we manage to keep some of the beds in bearing for many months at a time.” In the Field, Dec. 22, 1868, I stated that the manure for the mushroom-beds in the Royal Gardens, Frogmore, was not prepared in any elaborate way, but simply taken from a great heap fermenting in the yard, any parts of it that had become white from heat being moistened with water, and the whole being mixed with about a fourth part of loam. Mr. Cuthill, an authority on mushroom culture, tells us how the London market gardeners manage with their manure. As the material is brought home from the London stables, the short part is taken out of it, and the long litter is kept for the purpose of covering, as well as for forming the interior of ridges; for all mushroom-beds out of doors are made into ridges. The manure is not allowed to heat before it is put into the beds, if that can be prevented; for previously heated material does not produce such fine mushrooms. The fresher the horse-dung is, the longer the crop will last and every gardener who makes up beds with unheated droppings knows how superior they are to fermented manure. In his own practice Mr. C. depended a good deal on heavy tramping to “keep down fermentation” when droppings were used in a fresh state. The French, who are great mushroom growers, allow the manure to heat first, but treat it very simply. They prepare it in the open air, first removing any pieces of wood or other extraneous matter that may have been mixed with it, and then place it long and short in beds two feet thick, or a little more, pressing it with the fork. When this is done, the mass or bed is well stamped, then thoroughly watered, and finally again pressed down by stamping. It is left in this state for eight or ten days, by which time it has begun to ferment, after which the bed ought to be well turned over and re-made on the same place, care being taken to place the manure that was near the sides at first towards the centre in the turning and re-making. The mass is now left for another ten days or so, at the end of which time the manure is about in proper condition for making the beds, either in the open air or in the caves. Sometimes it receives three turnings over, especially when the manure is long, and it occupies altogether about six weeks in preparation. As the wide heaps are turned over by the men, a water-cart remains alongside, and any portions of the mass that are dry and white from heat are moistened with water from a rose watering pot. This preparation shortens and mollifies the longer material considerably, mixes the mass well, and it is transferred to the caves in a slightly decomposed, well mixed, and moist, but not wet, condition. The French do not actually hammer or desperately tramp down the beds, as nearly all our writers on mushroom culture recommend, but press it pretty firmly; and I have seen as good crops on their light spongy beds as ever I have on those so firmly tramped down. I might give other striking instances of the diversity of opinion on this subject, but it is needless to multiply them. My conclusions respecting the preparation of the manure for mushrooms are as follows:—1. That very careful preparation and frequent turning over of the manure undercover are not necessary to success, and that it is quite needless to prepare the manure under cover, except when it is gathered in a very small quantity, so that a heavy rain or snow would saturate it. Where, however, the culture is pursued on a very small scale, and, it may be, only one bed made, it is best to keep it in a covered shed. 2. That carefully picked droppings are not essential, though they may be more convenient. Excellent crops are gathered from beds made with ordinary stable manure, droppings and long materials mixed as they come; but when the manure is used as it comes from the stable, it should be allowed to ferment before being used. 3. That the best way of preparing manure for the general culture of mushrooms indoors, is to gather [14] [15] [16] [17] [18] it in some firm spot, and allow it to lose its fierce heat. As it is usually gathered in an irregular way, precise directions as to turning over cannot well be given; but I am convinced that one turning will suffice when it has arrived at a strong heat, and then it should be thrown together for a week or so, when, in being disturbed and removed to make the bed or beds, its strong heat will be sufficiently subdued. Where large quantities of stable manure are in a fermenting state, there should be little difficulty in selecting material to form a bed at any time. Should it have spent its heat overmuch, it would be easy to revive it with some fresh droppings. 4. That stable manure may be used when fresh, but it should be always mixed with more than a fourth of good loamy soil. If this be kept under cover, or stacked so that it may be had in a rather dry condition, so much the better, especially if the fresh manure, &c., should be over moist. Beds thus made are most suited for cool sheds and the open gardens. 5. That a portion, say nearly one-fifth to one-third, of good and rather dry loam may always be advantageously mixed with the stable manure; the fresher the materials, the more loam should be used. In all cases it helps to solidify the bed, and it is probable that the addition of the loam adds to the fertility and duration of the bed. 6. That a thickness of from one foot to fifteen inches for the beds in an artificially heated house is quite sufficient. Eighteen inches will not be too much for beds made in sheds, though I have seen excellent crops on beds only a foot thick, in common sheds with leaky sides. All beds made indoors should be flat and firmly beaten down, though the absence of firmness is not, as some think, sufficient to account for want of success. I will now quote a few words from Mr. Ayres on other materials for forming mushroom-beds than stable manure. He has given this, like almost every important subject in the range of horticulture, some attention. First among these may be mentioned sawdust which has been used for bedding horses or for riding-school tracks. Such a substance, thoroughly impregnated with urine and mixed with horse-droppings, forms an excellent material for mushroom-beds, especially if mixed with one-fourth of good fibrous loam. Such materials mixed and fermented together, and thrown into a bed a foot or eighteen inches in thickness, according to the temperature of the shed in which the bed is made, will be found to form capital material for growing this esculent, especially as it retains the heat for a long time. The worst of it is that the material is almost valueless after it has served the first purpose; and used as dung upon light land is rather injurious than otherwise. Then you may use leaves and loam, in the proportion of one part of the latter, in a turfy state, to four or five of fermenting leaves. These may be recently gathered from the trees, and should be allowed to attain a brisk heat before the loam is added, and then, after sweating for a week or ten days, may be turned, mixing the materials intimately together, and then the mass may be formed into a bed. A mushroom-bed of this kind should not be less than fifteen inches in thickness when thoroughly consolidated; and when so managed it will grow mushrooms just as well as dung. The sweepings of our streets and cattle markets, especially those parts that are paved and much frequented by horses—as, for example, cabstands, &c.—if collected when dry, and fermented a little, yield capital material for beds. Here from the cattle market we have the dung of horses, sheep, and cows mixed together in a finely divided state, the heating of which is gentle and regular. Material of this kind procured on dry days, thrown together to ferment once or twice, and then made into well-consolidated beds, will produce mushrooms of the finest quality, and continue in bearing a very long time. It is of the first importance that this material be collected in a dry state, as of course the slush of the streets would not do at all. Equal proportions of street sweepings and fresh leaves, properly fermented and mixed with loam, would perhaps make as good material for growing mushrooms as need be obtained. Of course the sweepings from those parts of the town most frequented by horses will be the best for the purpose I am writing about. The idea of mushrooms ceasing to be prolific from the exhaustion of the active manure in the bed, I have mooted before. Lately several experiments have been tried which convince me that by taking three portions of recently- gathered leaves to one of turfy loam, and working them well together until the mass attains the desired temperature, sprinkling it, as the work of turning proceeds, with liquid direct from the stables, and forming this into a bed treated in the usual manner, it will give just as good mushrooms as the best horse manure in the world. It is the ammonia that is wanted for this crop, with a gentle heat. Secure these two things, and, with ordinary care, success is certain. Before making the beds, while the material is in preparation, all particles of old wood, twigs, &c., that are found in the manure should be removed, as indeed should any extraneous matters likely to prove offensive or useless. The best time for making mushroom-beds, where they are not regularly made in succession throughout the autumn and winter months, as they ought to be where there is abundance of material and a good mushroom-house, is in August and September, as in the early autumn months the natural heat is sufficient to cause the spawn to germinate freely, and beds made then ought to bear freely before and up to Christmas, and during autumn. When making the bed, the chief object to bear in mind is the equal placing of the material. It should be well mixed and regularly and firmly placed so that the whole may be of a similar texture. Some heavily tramp and pound their beds to secure firmness; moderately done this is beneficial; thoroughly equable pressure with the fork, when the fork can be used, will with the pressure of firm earthing be sufficient; when beds are made on elevated benches in boxes, and in all positions where but a slight body of material is used, and where firmness cannot result from the general pressure of the mass, some kind of pressure with a wooden mallet or the like must be employed. The beds once made, we next arrive at the spawning, and will first inquire, What is spawn? CHAPTER III. [19] [20] [21] [22] [23] MUSHROOM-SPAWN. The first thing we have to determine is, What is spawn? Generally, the spawn, or what in scientific language is called the mycelium, is supposed to be analogous to seed, while it really is what may be termed the vegetation of the plant, or something analogous to roots, stems, and leaves of ordinary plants, the visible part or stem, head and gills, of the mushroom being, in fact, the fructification, though in such an apparent preponderance to the other parts. A knowledge of the anatomy and life-history of the mushroom is not necessary to the cultivator, and is not familiar even to those who make of mushrooms a study. We know that the gills are simply surfaces on which germs or spores are produced. The membrane that covers the spore plates of a single mushroom would cover a large space if spread out, and the spores are counted by myriads. We can see them clearly enough under the microscope—can see in what manner they are borne on and fixed to the gills; but of the history of their lives, from the time they fall from the surfaces on which they were born, till the “young mushroom” or inflorescence is vigorously pushing up from the mass of delicate vegetation which they have given rise to in earth or decaying manure, we know nothing. However, the preparation of the spawn, and the subsequent management of it in the mushroom-bed, are the matters which really concern us. How is spawn obtained in the first instance? It is found in a natural state in half-decomposed manure-heaps, in places where horse-droppings have accumulated and been kept dry, in riding-schools, sheds to which horses have long had access, in “mill tracks” under cover, in pastures, in partially decayed hotbeds, &c., and rarely or never in very moist or saturated materials. This spawn, sometimes termed “natural” in this country, and called by the French “virgin spawn,” is the best that can be obtained, and should be used in preference wherever it can be found. To use it, all that has to be done is to divide the material permeated by the white spawn into pieces a few inches square, and say an inch or more thick. They will of course break up irregularly, but all should be used, whether of the size of a bean, or nearly that of the open hand. Then they are inserted into the surface of the mushroom-beds in the ordinary way. In nearly every country place, and in numerous suburban ones, in fact, in most places where horses are kept, opportunities of finding this spawn occur. Its white, filamentous, and downy threads have the odour of mushrooms, and the spawn is, therefore, very easily recognised. It should be generally known that it need not be used when found, but may be dried, and kept for use in a dry place for years, and has been known to keep as long as fourteen years. It must not be supposed that it is only the hard bricks described further on that keep thus. The French spawn is in much looser and lighter material than that in which we usually find mycelium in a natural state, and it keeps quite as long as ours. To preserve spawn found in a natural state, nothing more is required than to take up carefully the parts of the manure in which it is found, not breaking them up more than may be necessary, and placing both large and small pieces loosely in rough shallow hampers. These should be placed in some dry airy loft or shed till thoroughly dry, and afterwards kept in some perfectly dry place, packed in rough boxes till wanted for use. Fig. 11. Brick mushroom-spawn. But inasmuch as in this country, at present, but little mushroom-spawn is required in any one place, the rule is to obtain artificial spawn in the form of hard bricks. This spawn is made from horse-droppings and some cowdung and road scrapings beaten up into a mortar-like consistency in a shed, and then formed into bricks, slightly differing in shape with different makers, but usually thinner and wider than common building bricks. Various recipes are given for mixing the materials for the bricks, and among them the following are about the best:—1. Horse-droppings the chief part, cowdung a fourth, and the remainder loam. 2. Fresh horse-droppings mixed with short litter the greater part, cowdung one third, and the rest mould or loam. 3. Horsedung, cowdung, and loam in equal parts. These bricks are placed in some dry, airy place, and when half dry, a little bit of spawn about as big as a hazel nut, is placed in the centre of each; or sometimes, when the bricks are as wide as long, a particle is put near each corner, just inserted below the surface, and plastered over with the composition of which the bricks are made. When the bricks are nearly dry, they are placed on a hotbed about a foot thick, in a shed or dry place. On this the bricks are piled, or placed rather openly and loosely, and covered over with litter, so that the heat may circulate equably amongst them. The temperature should not rise more than a degree or two above 60 degrees; if it does, it may easily be modified by reducing or removing the covering of litter. The makers frequently examine the bricks during the process, and when the spawn has been found to spread throughout a brick like a fine white mould, it is removed, and allowed to dry for future use in a dark, dry place. If allowed to go further than the fine white mould stage, and form threads and tubercles in the bricks, it has then attained to a higher degree of development than is consistent with preserving its vegetative powers, and therefore it should be removed from the bed in the fine mould stage. This is the kind of mushroom spawn mostly in use in our gardens, and it is usually very hard in texture. [24] [25] [26] [27] Fig. 12. Mill-track mushroom-spawn. There is a kind of spawn used in some gardens called mill-track mushroom-spawn, which is made in a more simple manner than the preceding. It would seem to be simply spawn that has spread through the thoroughly amalgamated droppings of a mill-track. The material is rather soft and free in texture, is usually sold in large and somewhat irregular lumps, and is much used by some cultivators. Fig. 13. Parisian mushroom-spawn. Finally, we have the French mushroom-spawn, which differs from our own in not being in bricks or solid lumps, but in rather light masses of scarcely half decomposed, comparatively loose and dry litter. This spawn is obtained by preparing a little bed as if for mushrooms in the ordinary way, and spawning it with morsels of virgin spawn, if that is obtainable; and then when the spawn has spread through it, the bed is broken up and used for spawning beds in the caves, or dried and preserved for sale. It is sold in small boxes, and is fit for insertion when pulled in rather thin pieces, about half the size of the open hand; but in separating it, it divides into many pieces, of all sizes, every particle of which should be used. The small particles should be strewn broadcast over the bed after the larger pieces have been inserted. This applies to the other kinds. In consequence of the open porous nature of the French mushroom-spawn, it is likely to be immediately affected by the heat and moisture of the genially warm manure forming the mushroom-bed, and on that account alone presents some advantages. It has recently been introduced for the first time, and probably will soon be tested by many growers. Spawn, in the common sense of the word, may be dispensed with by well amalgamating manure, loam, and old mushroom-beds, or leaf-mould containing traces of spawn, and these formed into beds about a foot thick in the mushroom-house, and covered with earth, produce without any further spawning; but the plan is not so simple or advantageous as that more commonly pursued. There is no necessity for purchasing artificial spawn at all where mushrooms are regularly grown. Nor is there in any case except at the commencement, or to guard against one’s own spawn proving bad. To secure good spawn, we have only to do as the French growers do: take a portion of a bed where it is thoroughly permeated by the spawn and before it begins to bear, and preserve it for future use. Of the efficacy of this sort of spawn, if any proof were needed in addition to the fine crops the Parisian growers gather, it will be found in the following statement from Mr. Ayres:— “A short time back, attention was directed to the superior quality of French mushroom-spawn, and as a natural consequence several London seedsmen imported it for sale. Some months back I obtained possession of a stable, and, wishing to grow mushrooms in it, procured a few tons of horse manure, just as it came from the dung-pit of the hotel stables. It was very wet, and consequently when thrown together it heated violently. However, by frequent turning for a week or ten days this tendency was reduced, and then five beds were formed of it, adding one-fourth of perfectly dry soil from a cucumber-house. I say perfectly dry, because the soil had lain in the house for fifteen or eighteen months without receiving a drop of water, and therefore may almost be considered as thoroughly dry. Intimately mixed with the fermenting dung, it had the tendency that I desired—viz., subdued the excessive moisture, and, after the bed had been made up a week, brought it to the temperature necessary to receive the spawn. “Having great faith in the good qualities of fresh loam from an old pasture for the production of mushrooms of [28] [29] [30] superior quality, I had a quantity dried and warmed. I had a coat of this three inches thick laid over each bed, and then forked carefully in, taking care to mix the soil and dung as intimately as possible. Re-formed and left for a few days the beds attained the necessary warmth; then they were made quite firm, and were ready for spawning. “For this purpose I had procured two boxes of the French spawn from Messrs. Barr and Sugden, of Covent Garden. It was light, loose, flaky, chaffy stuff, and so dry that I had some fear whether its vegetating power had not been dried out of it. But the spawn had been bought for experiment, and therefore the experiment must be carried out. “Raking about two inches of the material from the surface of each bed, pieces of the flaky spawn were laid down, at about ten inches or a foot apart, all over the beds; the fine portions of the spawn were then scattered over the beds, patted down firmly with the back of a spade, and then the surface material was returned, and the whole made as firm as possible. In passing, it may not be out of place to remark that spawning in this manner must be guided, or rather governed, by the state of the material of the bed. If it is not sufficiently cooled, it will be safer to make holes in the usual manner for the spawn; but if in a fit state, then I think the broadcast spawning and earthing, as before described, is the best plan. The disturbed portion of the beds having regained its heat, and there being no fear of its overheating, the beds were immediately earthed two inches thick with fresh loam, beaten quite firm, and then covered with a thin layer of dry hay. “Not liking to entrust my chance of mushrooms entirely to the new material, the French spawn, two beds were spawned at the same time and in the same manner with native spawn. Owing to the large size of the stable, and the unusually cold, piercing weather at the end of the year (1869), the beds lost so much heat that I had some misgivings whether they would not prove a failure; but finding, subsequently, that the spawn was working, I gave each bed (the surface being rather dry) a good syringing with water at the temperature of 80 deg., covered it with clean dry mats, and then returned the hay. The beds are now a sheet of the ‘pearl of the fields,’ some of the patches as large as a cheese- plate, and the whole in most promising condition—so promising that, with proper attention, I have no doubt they will yield a good supply of mushrooms for many months. To secure this continuous bearing, farmyard manure-water and salt, at proper times, should not be spared; while, as soon as the flush of the first crop is over, the beds may receive a thorough soaking of manure-water at a temperature of not less than 80 deg., be re-earthed with fresh soil, and covered down with mats and hay. In this manner we always get a second crop little inferior to the first one, and sometimes much superior.” CHAPTER IV. SPAWNING AND AFTER-TREATMENT. Heat and Protection. The temperature of the material of the beds should never, at spawning time, exceed 80 degrees Fahr.—about 70 is the most suitable regular temperature; and that of the mushroom-house should range between 50 and 60 degrees—not lower than 50. Assuming the materials to have been turned once after having heated, and again disturbed previous to being made into beds, they ought to be in a condition for spawning from ten to twelve days after being put together. It need hardly be said that this regularity of temperature can only be secured in properly-formed mushroom-houses. Where mushrooms are grown in these, with double ceilings and close-fitting shutters and doors, almost impervious to external influences, and where fresh beds are made from time to time, little or no artificial heat from pipes is required, though it is as well to have some at command in the case of unusually severe weather, or a break in the succession of beds, which would cause a deficiency of heat from fermenting materials. A covering of hay or dry litter is necessary for beds formed in the open air, and also for beds made in cool, half-open sheds; but not for those in regularly heated mushroom-houses or caves, in which there is a still, steady temperature. It should be about a foot thick, and should be immediately removed when it becomes wet or mouldy. This covering should be applied whenever the temperature of the bed begins to fall. It should not be used in any case where the temperature will permit of dispensing with it, as it is troublesome, and sometimes encourages insects. The heat of a bed may be reduced by opening holes six or eight inches deep with a thick pointed dibber, here and there, but it is only in exceptional cases that this is advisable, and it is desirable to husband all the ammonia and heat of the bed. The earthing over and firming of a bed has a tendency to subdue the heat in it. Where large sloping beds, say three feet deep at back, are made against the wall, I have seen Λ- shaped crates put beneath them at six feet apart, so as to permit of heating them by fresh supplies of manure. It is, however, a plan possessing little claim to general use. It is best not to depend on the hand, as is commonly done, for ascertaining the heat of the beds. Thermometers fixed on sticks of convenient size, to thrust in the beds, are sold, and remove all excuse for vagueness in this matter. Coverings of litter are sometimes useful in “drawing-up the heat” in a bed that has become somewhat chilled. Spawning. This is the phase of the culture which requires most attention, as to get the spawn to run regularly through the bed is to be nearly certain of securing a good crop. In this respect there do not seem to be so many differences of opinion [31] [32] [33] [34] [35]