In open, airy greenhouses it is always well to inclose the mushroom beds in box casings and with sash or shutter coverings, to prevent draughts and fluctuations of temperature and atmospheric moisture. This can easily be done by making the sides a board and a half (fifteen inches), or two boards (twenty inches) high, and covering over with light wooden shutters, sashes, or muslin or paper-covered light frames. See Fig. 11.

=Ammonia Arising.=--Ammonia arising from the manure of the mushroom beds in the greenhouse may be injurious to the other inmates of the greenhouse. If the manure has been well prepared before it was introduced into the greenhouse, the ammonia arising from it will not, in the least degree, injure any other plants or flowers that may be in the house; but if the manure is fresh, hot, and rank, the opposite will be the case. Beds in greenhouses should always be made up of manure that has been well prepared beforehand out of doors or in a shed, and as it is brought into the greenhouse it should at once be built solidly into the beds. Then very little steam will arise from the beds; in fact, it will be imperceptible to sight or smell.

CHAPTER VI.

GROWING MUSHROOMS IN THE FIELDS.

Under suitable conditions we can grow mushrooms easily and abundantly in the open fields, and the planting of the sp.a.w.n is all the trouble they will cause us. During the late summer and fall months mushrooms often appear spontaneously and in great quant.i.ty in our open pastures, but in their natural condition they are an uncertain crop, as in one year they may occur in the greatest abundance, and in the next perhaps none can be found in the fields in which they had been so numerous the previous year. Why this should be so is not very clear. The popular opinion is that after a dry summer mushrooms abound in the fields, but after a wet summer they are a very scarce crop; and the inference is that the moisture has killed the sp.a.w.n in the ground. This may be true to a certain extent, but how does it happen--as it certainly often does--that good sp.a.w.n planted by hand in the fields in early summer will produce mushrooms toward fall no matter whether the summer has been wet or dry?

At the same time, it is true that a wet spell immediately succeeding the planting of the sp.a.w.n will kill a great deal of it.

As a rule, wild mushrooms abound most in rich, old, well-drained, rolling pasture lands, and avoid dry, sandy, or wet places, or the neighborhood of trees and bushes. In attempting to cultivate them in the open fields we should endeavor to provide similar conditions. Then the chief requisite is good sp.a.w.n, for without this we can not raise mushrooms.

About the middle of June take a sharp spade in the pasture, make =V= or =T=-shaped cuts in the gra.s.s sod about four inches deep and raise one side enough to allow the insertion of a bit of sp.a.w.n two to three inches square under it, so that it shall be about two inches below the surface, then tamp the sod down. By cutting and raising the sod in this way, without breaking it off, it is not as likely to die of drought in summer. In this way plant as much or little as may be desired and at distances of three, four, or more feet apart. During the following August or September the mushrooms should show themselves, and continue in bearing for several weeks.

Mr. Henshaw, of Staten Island, who has been very successful in growing mushrooms in the fields as well as indoors, writes to me as follows: "You ask me to give you my plan of growing mushrooms in the fields during the summer. It is very simple. About the end of June, or as soon as dry weather sets in, we remove the old beds from our mushroom house, and if there should be any live sp.a.w.n in the bottom of our beds we put it in a wheelbarrow and take it to the field, where we plant it in the open places, but never under trees. In planting, we lift a sod and put a shovelful of the manure containing the sp.a.w.n in the hole, then replace the sod and beat it down firm; this we do at distances of twelve feet apart. If we have no live sp.a.w.n from our indoor beds we take the common brick sp.a.w.n, and put about a quarter of a brick into each hole, returning and beating down the sod as already stated. This is all that is done. If there comes a dry time after the sp.a.w.n is put in the pasture we are sure to have a good supply of mushrooms in the fall."

A few years ago Carter & Co., seedsmen, London, sent this to one of the gardening periodicals: "The following mode of growing mushrooms in meadows by one of our customers may be interesting to your readers: In March (May would be soon enough here) he begins to collect droppings from the stables. These, when enough have been gathered together, are taken into the meadow, where holes dug here and there about one foot or eighteen inches square are filled with them, the soil removed being scattered over the surrounding gra.s.s. When all the holes have been filled and made solid he then places two or three pieces of sp.a.w.n about one inch square in each hole, treads all down firmly, replaces the turf and beats it tightly down. Under this system, in August and September mushrooms appear without fail in abundance and without any further care.

The method is simple and the result certain. Therefore all who happen to have a meadow, paddock, or gra.s.s field, and are fond of mushrooms, should try the experiment.... In the case in question fresh holes were sp.a.w.ned every year."

CHAPTER VII.

MANURE FOR MUSHROOM BEDS.

In order to grow mushrooms successfully and profitably a supply of fresh horse manure is needed, and this should be the very best that is made, either at home or bought from other stables. The questions of manure and sp.a.w.n are the most important that we have to deal with. Very few make their own sp.a.w.n, as it is bought and accepted upon its good looks,--often rather deceptive,--but the manure business is entirely in our own hands, and success with it depends absolutely upon ourselves. We can not reasonably expect good results from poor manure nor from ill-prepared manure. It is only from the very best of horse manure prepared in the very best fashion that we can hope for the very best crops of the best mushrooms.

=Horse Manure.=--There are various kinds of horse manure, differing materially in their worth for mushroom beds. The kind of manure depends upon the condition of the horses, how they are housed, fed, and bedded, and how the manure is taken care of. But while the manure of all healthy animals is useful for our purpose, there still is a great choice in horse manure. If we are dependent upon our home supply we may use and make the best of what we have, but if we have to buy the manure we should be very particular to select the best kind of manure and accept of no other.

The very best manure is that from strong, healthy, hard-worked, well-kept animals that are liberally fed with hard food, as timothy hay and grain, and bedded with straw. And if the bedding be pretty well wetted with urine and trampled under the horses' feet, so much the better; indeed, this is one reason why manure from farm and teamsters'

stables is better than that from stylish establishments, where everything is kept so scrupulously dry and clean.

[Ill.u.s.tration: FIG. 19. PERSPECTIVE VIEW OF THE DOSORIS MUSHROOM CELLAR.]

The fresher the manure is the better, still manure that is not perfectly fresh may also be quite good. Stable manure may acc.u.mulate in a cellar for a couple of months, and still be first rate. After our hotbed season is over I stack our stable manure high in the yard, and from June until August, as the manure is taken away from the stable each day, it is piled on the top of this stack. My object is to keep it so dry that it can neither heat nor rot. In August the stack is broken down and the best manure shaken out to one side for mushrooms, and the long straw and rotted parts thrown to the other side. This short manure, when moistened with water and thrown into a heap, exposed to the sun for a day or two, will heat up briskly. The beds ill.u.s.trated in Fig. 19 were made from manure prepared in this way in August.

In the case of quite fresh manure, let it acc.u.mulate for a few days, or a fortnight, even, until there is enough of it to make up a bed, and then prepare it. Be very particular to prevent, from the first, its heating violently or "burning" while acc.u.mulating in the pile. Beds made from very fresh manure respond quickly and generously. The crop comes in heavily to begin with, and continues bearing largely while it lasts, but its duration is usually shorter than in the case of a bed made up of less fresh manure. But altogether it yields a better and heavier crop than a bed that comes in more gradually and lasts longer, and the mushrooms are of the finest quality.

Some growers use the droppings only, and reject all of the strawy part, or as much of it as they can conveniently shake out. This gives them an excellent manure and perhaps the very best for use on a small scale or in small beds. When mushrooms are to be grown in boxes, narrow troughs, half barrels, and other confined quarters, it is well to concentrate the manure as much as possible--use all the droppings and as little straw as you can. But droppings alone for large beds would take too much manure and cost too much, and they would not be any better than with a rougher manure.

Always preserve the wet, strawy part of the manure, along with the droppings, and mix and ferment them together, and in this way not only add largely to the bulk of the pile, but secure the benefits afforded by the urine without reducing, in any way, the strength or fermenting properties of the manure. Shake out all the rank, dry, strawy part of the manure and lay it aside for other purposes. This may be of further use as bedding in the stables, covering the mushroom beds after they have been made up, or for hotbeds; if well wetted with stable drainings, or even plain water, it forms a ready heating material.

Many a time when we have been short of home-made manure I have bought some loads here and there from different stables in the village, and mixed all together and made it into beds with excellent results.

Sometimes when the manure under preparation had been rather old and cool, I have added a fifth or tenth part of fresh droppings to it, with very quickening effect in heating and apparent benefit to the crop.

It is generally believed that the manure of entire horses is better for mushrooms than that of other horses, but positive evidence in this direction has never come under my observation. Some practical men a.s.sert that there is no difference. Mr. John G. Gardner, at the Rancocas Farm, who has had abundant opportunity to test this matter, tells me that he has given it a fair trial and been unable to find any difference in the quality or quant.i.ty of mushrooms raised from beds made from the manure of entire horses and those raised from beds made from the manure of other equally as well fed animals. But the Parisian growers insist that there is a difference in favor of entire horses, especially in the case of hard-worked animals such as are engaged in heavy carting.

Manure of horses that are largely fed with carrots is emphatically condemned by most writers on the cultivation of mushrooms; indeed, it is one of _the_ points in every book on mushrooms which I have read. Let us look at a few practical facts: There are at Dosoris two shelf beds in one cellar; each is thirty feet long, three feet wide, and nine inches deep, and both are bearing a very thick crop of mushrooms. The material in these beds consists of horse manure three parts and chopped sod loam one part, which had been mixed and fermented together from the first preparation. The manure was saved from the stables on the place in November, '88, the materials prepared in December, the beds built Dec.

17, sp.a.w.ned Dec. 24, molded over Dec. 31, and first mushrooms gathered Feb. 7, 1889. These beds bore well until the middle of April. The mushrooms did not average as large as they did on the deeper beds upon the floor of the cellar, but they ran about three-fourths to one ounce apiece, and a good many were more than this. It is most always the case, however, that the crop on thin shelf beds averages less than it does on thick floor beds, and especially is this noticeable after the first flush of the crop has been gathered, no matter what kind of fermenting material had been used. At the time when the manure used for these beds was being saved at the stable the horses were only very lightly worked, and to each horse was fed, in addition to hay and some oats and bran, about a third of a bushel of carrots a day. And this is the manure used for the late mushroom beds, and yet good crops and good mushrooms are produced. This is not only the experience of one year's practice but the regular routine of many.

Perhaps some one would like to ask: Do you consider the manure of carrot-fed horses as good as the manure of animals to which no carrots or other root crops had been fed? My answer is--decidedly not. While the manure of carrot-fed animals is not the best, at the same time it is good, and any one having plenty of it can also have plenty of mushrooms.

The complete denunciation of the manure of carrot-fed horses so emphatically stereotyped upon the minds and pens of horticultural writers is not always founded on fact.

=Manure of Mules.=--This is regarded as being next in value to that of entire horses, and some French growers go so far as to say that it is quite as good. Mr. John G. Gardner tells me of an extraordinary crop of mushrooms he once had which astonished that veteran, Samuel Henshaw, and that it was from beds made of manure from mule stables. Certainly the heaviest crop of mushrooms I ever did see was at Mr. Wilbur's place at South Bethlehem, Pa., four years ago, and the beds were of clean mule droppings from the coal mines. Mule manure can be had in quant.i.ty at our mule stock yards, which are in nearly every large city in the Middle and Southern States. Getting it from the mines costs more than it is worth, except as a fancy article; the men will not collect and save it for any reasonable price.

=Cellar Manure.=--Many stables have cellars under them into which the manure and urine are dropped at every day's cleaning. These cellars are not generally cleaned out before a good deal of manure has acc.u.mulated in them, say a few weeks', or a few months', or a winter's gathering, and it is commonly pretty well moistened by the urine. If this manure has not become too dry and "fire-fanged" in the cellar it is splendid for mushrooms. We buy a good deal of it, but are particular to reject the very dry and white-burned parts. Sometimes the manure from the cow-stables, as well as from the horse-stables, is dropped together into the cellar; then I would give less for the manure, especially if the cow manure predominated, because in the working it keeps too cold and wet and pasty; but if there is not cow manure enough to give the ma.s.s a pasty character it will make capital mushroom beds. Pigs often have the run of the manure-cellar, as is generally the case in farmyards. I would not use any part of this mixed pig manure. Mycelium evades hog manure; besides it is impure and malodorous, and a propagating bed for noxious insect vermin. It matters very little what kind of bedding is used, in the case of cellar manure, but I would not buy it if sawdust or salt hay had been used as bedding. Neither of these materials, in limited quant.i.ty, is deleterious to the mushrooms; at the same time, they are far less desirable than straw, field hay, German peat moss, or corn stalks, and there are risks enough in mushroom-growing without courting any that we can as well avoid.

=City Stable Manure.=--Around New York this can always be had in any quant.i.ty at a reasonable rate, and it is first-rate manure for mushroom beds. Market gardeners haul in a load of vegetables to market and bring back a load of manure; others may buy and haul home manure in the same way, or make arrangements with a teamster to do it for them. But the whole matter of city manure is now so deftly handled by agents, who make a special business of it, that we can get any quant.i.ty of manure, from a 500 lb bale to an unlimited number of loads, and of most any quality, delivered near or far, inland or coastwise, at a fairly moderate price.

It is the city stable manure that nearly all our large market growers use for their mushroom beds. When they get it at the stables and cart it home themselves they know what they are handling, and should take only fresh horse dung. In ordering it of an agent be particular to arrange for the freshest and cleanest, pure horse manure. They will get it for you. We get several hundreds of loads of this selected manure from them every year for hotbeds, and find it excellent. We also get 1000 to 2000 loads of the common New York stable manure a year for our general outdoor crops, and it also is capital manure in its way, but not so good as the selected manure for mushrooms. It is mixed a little and smells very rank, and in mushroom beds usually produces a good deal of spurious fungi. Most all of our largest mushroom growers, Van Siclen of Jamaica, Denton of Woodhaven, Connard of Hoboken, and others, live within easy hauling distance of the city, and are able to select and get the very choicest manure at a very cheap rate.

=Baled Manure.=--Within a year or two a good deal of our city horse manure has been put up in bales and thus shipped and sold. Each bale contains from 350 to nearly 500 lbs, and is made up, pressed and tied in about the same way as baled hay. The princ.i.p.al advantages of the bales are these: Only the cleanest horse manure is put up in this way; cow manure, offal, spent hops, or other short or soft manures are not included in the bales, nor, on account of shipping considerations, are malodorous manures of any sort permitted in them. The railroads allow baled manure to be put off on their platforms, and closer to their stations than they would allow loose manure; and it often happens that an agent will send a carload to a railroad station and dump it off there so that the people around who have only small garden lots can have an opportunity of buying one or more bales, just as they need it, and without, as is generally the case, having to buy a whole load when they need only half a load. These bales are quite a boon to people who would like to have a small bed of mushrooms in their cellar and who have no other manure. Bring home one or more bales, open them, spread out the manure a little, and when it heats turn it a few times, and it will soon be ready for use. Or if you do not wish to litter up the place, roll the bales into the cellar, shed, or wherever else you wish to make use of them, and mix about one-fourth of their bulk of loam with the manure and make up the bed at once.

The Board of Health of New York city is very emphatic in its endeavors to rid the city of any acc.u.mulation of manure and, a year ago, had under consideration a plan to compel the manure agents, for sanitary reasons, to bale the stable manure. And perhaps this is the reason why it is so easily procured, to wit: A New York gentleman, desirous of engaging in the mushroom-growing business, writes me: "I get my manure from the city in bales. All it costs me is the freight to my place at White Plains."

Lucky gentleman! With any amount of the best kind of stable manure gratis, no wonder he wishes to embark in the mushroom ship.

=Cow Manure.=--This is sometimes used with horse manure in forming the materials for a mushroom bed, and several European writers are emphatic in advocating its use. But I have tried it time and time again, and in various ways, and am satisfied that it has no advantage whatever over plain horse manure, if, indeed, it is as good. It is not used by the market growers in this country.

The best kind of cow manure is said to be the dry chips gathered from the open pastures; these are brought home, chopped up fine and mixed with horse manure. The time and expense incurred in collecting and chopping these "chips" completely overreach any advantages that might be derived from them, no matter how desirable they may be. The next best kind of cow manure is that of stall-fed cattle, to which dry food only, as hay and grain, is fed. This is seldom obtainable except in winter, and is then available for spring beds only. This I have used freely.

One-third of it to two-thirds of dry horse manure works up very well, heats moderately, retains its warmth a long time, also its moisture without any tendency to pastiness; the mycelium travels through it beautifully, and it bears fine mushrooms. Still, it is no better than plain horse manure. The poorest kind of cow manure is the fresh manure of cattle fed with green gra.s.s, ensilage, and root crops; indeed, such manure can not be used alone; it needs to be freely mixed with some absorbent, as dry loam, German moss, dry horse droppings, and the like, and even then I have utterly failed to perceive its advantages; it is a dirty ma.s.s to work, and quite cold.

In the manufacture of sp.a.w.n, however, cow manure is a requisite ingredient, and here again the manure of dry fed animals is better than that of those fed with green and other soft food. But my chief objection to the use of cow manure in the mushroom beds is that it is a favorite breeding and feeding place for hosts of pernicious bugs and grubs and earth worms,--creatures that we had better repel from, rather than encourage in, our mushroom beds.

=German Peat Moss Stable Manure for Mushroom Beds.=--Although I have not yet had an opportunity of trying this material for mushroom beds, Mr.

Gardner, of Jobstown, has great faith in it; so, too, has that prince of English mushroom growers, Richard Gilbert, of Burghley, who relates his success with it in growing mushrooms in the English garden papers. This peat moss is a comparatively new thing in this country, and is used in place of straw for bedding horses. It is a great absorbent and soaks up much of the urine that, were straw used instead, would be likely to pa.s.s off into the drains. To this is ascribed its great virtue in mushroom culture. It should be mixed with loam when used for mushroom beds.

[Ill.u.s.tration: FIG. 20. BALE OF GERMAN PEAT MOSS.]

=Sawdust Stable Manure for Mushroom Beds.=--This is the manure obtained from stables where sawdust has been used for bedding for the horses. It is a good absorbent and retains considerable of the stable wettings.

Such manure ferments well, makes up nicely into beds, the mycelium runs well in it, and good mushrooms are produced from it. But if I could get any other fairly good manure I wouldn't use it. I remember seeing it at Mr. Henshaw's place some years ago. He had bought a quant.i.ty of fresh stable manure from the Brighton coal yards, where sawdust had been used for bedding for the horses, and this he used for his mushroom beds. I went back again in a few months to see the bed in bearing, but it was not a success. At the same time, some European growers record great success with sawdust stable manure. George Bolas, Hopton, Wirkeworth, England, sent specimens of mushrooms that he grew on sawdust manure beds to the editor of the _Garden_, who p.r.o.nounced them "in every way excellent." Mr. Bolas says: "In making up the bed I mixed about one-third of burnt earth with the sawdust, sand, and droppings. The mushrooms were longer in coming up than usual, the bed being in a close shed, without any heat whatever. They have, however, far exceeded my expectations."

Richard Gilbert, of Burghley, also wrote to the _Garden_, April 25, 1885: "There is nothing new in growing mushrooms in sawdust. I have done it here for years past; that is to say, after it had done service as a bed for horses, and got intermixed with their droppings. I have never been able to detect the least difference in size or quality between mushrooms grown in sawdust and those produced in the ordinary way."

=Tree Leaves.=--Forest tree leaves are often used for mushroom beds, sometimes alone, instead of manure, but more frequently mixed with horse manure to increase the bulk of the fermenting material. Oak tree leaves are the best; quick-rotting leaves, like those of the chestnut, maple, or linden, are not so good, and those of coniferous trees are of no use whatever. As the leaves must be in a condition to heat readily they should be fresh; such are easily secured before winter sets in, but in spring, after lying out under the winter's snow and rain, their "vitality" is mostly gone. But we can secure a large lot of dry leaves in the fall and pile them where they will keep dry until required for use. As needed we can prepare a part of this pile by wetting the leaves, taking them under cover to a warm south-facing shed, and otherwise a.s.sisting fermentation just as if we were preparing for a hotbed. While moistening the leaves with clean water will induce a good fermentation, wetting them with liquid from the horse-stable urine tanks will cause a brisk heat, and for mushrooms produce more genial conditions.

Mushroom beds composed in whole or part of fermenting tree leaves should be much deeper than would be necessary were horse manure alone used; for half leaves and half manure, say fifteen inches deep; for all leaves, say twenty to thirty inches deep.

While mushroom sp.a.w.n will run freely in leaf beds and we can get good mushrooms from them, my experience has satisfied me that we do not get as fine crops from these beds or any modification of them as from the ordinary stable manure beds. And we can not wonder much at this, considering that the wild mushroom is scarcely ever found in the neighborhood of trees or where leaf mold deposits occur.

=Spent Hops.=--We can make good use of this in one way. If we are short of good materials for a mushroom bed, we can first make up the beds eight or ten inches deep with fermenting spent hops, and above this lay a four or five inch layer of horse manure, or this and loam mixed. The hops will keep up the warmth, and the manure affords a congenial home for the mushroom sp.a.w.n. But we should never use spent hops alone, nor so near the surface of the beds that the sp.a.w.n will have to travel through it.

Spent hops can be had for nothing, and our city brewers even pay a premium to the manure agents to take the hops away.