CHAPTER XI.
SPAWNING THE BEDS.
After the mushroom bed is made up it should, within a few days, warm to a temperature of 110° to 120°. Carefully observe this, and never spawn a bed when the heat is rising, or when it is warmer than 100°, but always when it is on the decline and under 90°. In this there is perfect safety. Have a ground thermometer and keep it plunged in the bed; by pulling it out and looking at it one can know exactly the temperature of the bed. Have a few straight, smooth stakes, like short walking canes, and stick the end of these into the bed, twelve to twenty feet apart; by pulling them out and feeling them with the hand one can tell pretty closely what the temperature of the bed is.
All practical mushroom growers know that if the temperature of a twelve inch thick bed at seven inches from the surface is 100°, that within an inch of the surface of the bed will only be about 95° indoors, and 85° to 90° out of doors. Also, that when the heat of the manure is on the decline it falls quite rapidly, five, often ten degrees, a day, till it reaches about 75°, and between that and 65° it may rest for weeks.
Some years ago I gave considerable attention to this matter of spawning beds at different temperatures. Spawn planted as soon as the bed was made (five days after spawning the heat in interior of bed ran up to 123°) yielded no mushrooms, the mycelium being killed. The same was the case in all beds where the spawn had been planted before the heat in the beds had attained its maximum (120° or over). Where the heat in the middle of the bed never reached 115°, the spawn put in when the bed was made, and molded over the same day, yielded a small crop of mushrooms. A bed in which the heat was declining was spawned at 110°; this bore a very good crop, and at 100° and under to 65° good crops in every case were secured, with several days' delay in bearing in the case of the lowest temperatures. But notwithstanding these facts, my advice to all beginners in mushroom growing is, wait until the heat of the bed is on the decline and fallen to at least 90°, before inserting the spawn.
Writing to me about spawning his beds, Mr. Withington, of New Jersey, says: "I believe a bed spawned at 60° to 70°, and kept at 55° after the mushrooms appear, will give better results than one spawned at a higher temperature, say 90°."
Preparing the Spawn.—If brick spawn is used cut up the bricks (standard size) into ten or twelve pieces with a sharp hatchet, and avoid, as much as possible, making many crumbs, as is the case generally when a hammer or mallet is used in breaking the bricks. Extra large pieces of spawn are apt to produce large clumps of mushrooms, but this is not always an advantage, as when many mushrooms grow together in a clump they are apt to be somewhat undersized, and in gathering we can not pluck them all out clean enough so as not to leave a part of the "root" in the ground to poison the balance of the clump, in cases where several or many of them spring from one common base.
Inserting the Spawn.—When brick spawn is used plant the lumps about an inch deep under the surface of the manure, and about ten inches apart each way. If the spawn looks very good, and the lumps are large do not plant them quite so close as when the spawn shows less mycelium in it, and the lumps are small. Never use a dibber in planting spawn; simply make a hole in the manure with the fingers, insert the lump and cover it over at once, and as soon as the bed has been planted firm it well all over. Although the lumps are buried only an inch deep under the manure, we have to make a hole three or four inches deep to push the lump into to get it buried.
French or flake spawn is inserted in much the same way and at about the same distance, only, instead of cutting it up into lumps, we merely break it into flaky pieces about three inches long by an inch thick, and in planting it in the beds, in place of pushing it into the hole, lay in the flake on its flat side and at once cover it.
Many growers plant spawn a good deal deeper than I do, but I have never found any advantage in deep planting. In moderately warm beds, or beds that are likely to retain their heat for a considerable time, I am satisfied that shallow planting is better than deep planting. When we want to mold over our beds soon after spawning them, shallow planting is to be recommended. But if the beds are only 75° to 78°, before being spawned; then I think deep planting is better than shallow planting, because the genial temperature gives the mycelium a better start in life than would the cooler manure nearer the surface.
If there is any likelihood of the surface manure getting wet from the condensed moisture of the atmosphere, I would again cover over the beds with some hay or straw, and let it remain on until molding time. And if the bed is a little sluggish,—that is, cool,—this covering will help in keeping it warm. Outside beds should be molded over in three or four days after spawning; inside beds in eight to ten days.
Steeped Spawn.—As brick spawn is so hard and dry I have tried the effect of steeping it in tepid water before planting; some pieces were merely dipped in the water, and others allowed to soak in the pails one-half, one, five, and ten hours. The effect was prejudicial in every instance and ruinous in the case of the long-soaked pieces.
Flake Spawn.—"This is produced by breaking up the brick spawn into pieces about two inches square and mixing them in a heap of manure that is fermenting gently. After lying in this heap about three weeks it will be found one mass of spawn, and just in the right condition for running vigorously all through the bed in a very short time.... When flake spawn is used the appearance of the crop is from two to three weeks earlier than when brick spawn is used."—Mr. Henshaw, in first edition of "Henderson's Handbook of Plants." I have tried this method and given it careful attention, but the results were inferior to those obtained where plain, common brick spawn had been used at once.
In all my practice I have found that any disturbance of the spawn when in active growth which would cause a breaking, exposing, or arresting of the threads of the mycelium has always had a weakening influence upon it. I have transplanted pieces of working spawn from one bed to another, as the French growers do, but am satisfied that I get better crops and larger mushrooms from beds spawned with dry spawn than from beds planted with working spawn from any other beds.
CHAPTER XII.
LOAM FOR THE BEDS.
In growing mushrooms we need loam for casing the beds after they are spawned, topdressing the bearing beds when they first show signs of exhaustion, filling up the cavities in the surface of the beds caused by the removal of the mushroom stumps, and for mixing with manure to form the beds. The selection of soil depends a good deal on what kind of soil we have at hand, or can readily obtain.
The best kind of loam for every purpose in connection with mushroom-growing is rich, fresh, mellow soil, such as florists eagerly seek for potting and other greenhouse purposes. In early fall I get together a pile of fresh sod loam, that is, the top spit from a pasture field, but do not add any manure to it. Of course, while this contains a good deal of grassy sod there is much fine soil among it, and this is what I use for mushrooms. Before using it I break up the sods with a spade or fork, throw aside the very toughest parts of them, and use the finer earthy portion, but always in its rough state, and never sifted. The green, soddy parts that are not too rough are allowed to remain in the soil, for they do no harm whatever, either in arresting the mycelium or checking the mushrooms, and there is no danger that the grass would grow up and smother the mushrooms.
Common loam from an open, well-drained fallow field is good, and, if the soil is naturally rich, excellent for any purpose. But do not take it from the wet parts of the fields. Reject all stones, rough clods, tussocks, and the like. Such loam may be used at once.
Ordinary garden soil is used more frequently than any other sort, and altogether with highly satisfactory results. The greatest objection I have to it is the amount of insects it is apt to contain on account of its often repeated heavy manurings.
Roadside dirt, whether loamy or gritty, may also be used with good results. If free from weeds, sticks, stones and rough drift, it may be used at once, but it is much better to stack it in a pile to rot for a few months before using.
Sandy soil, such as occurs in the water-shed drifts along the roads and where it has been washed into the fields, is much inferior to stiffer and more fibrous earth.
I have used the rich dark colored soil from slopes and dry hollows in woods, and, odd though it may appear, as mushrooms do not naturally grow in woods, with success. But it is not as good as loam from the open field.
Peat soil or swamp muck that has been composted for two or three years has failed to give me good returns. The mushrooms will come up through it all right, but they do not take kindly to it.
Heavy, clayey loam is, in one way, excellent, in another, not so good. So long as we can keep it equably moist without making it muddy it is all right, but if we let it get a little too dry it cracks, and in this way breaks the threads of the spawn and ruins the mushrooms that were fed through them.
Loam Containing Old Manure.—Loam in which there is a good deal of old, undecomposed manure, such as the rich soil of our vegetable gardens, is unqualifiedly condemned by some writers because of the quantity of spurious and noxious fungi it is supposed to produce when used in mushroom beds. But I can not join in this denunciation because my experience does not justify it. This earth is the only kind used by many market gardeners, as they have no other, and certainly without apparent injurious effect. When I was connected with the London market gardens, some twenty years ago, Steele, Bagley, Broadbent, and the other large mushroom growers in the Fulham Fields cased all of their beds with the common garden soil—perhaps the most manure-filled soil on the face of the earth—and spurious fungi never troubled them. Indeed, I can not understand why it should produce baneful crops of toadstools when used in mushroom beds, and no toadstools when used for other horticultural purposes, as on our carnation benches in greenhouses, in our lettuce or cucumber beds, or in the case of potted plants. True, spurious fungi may appear in the earth on our greenhouse benches or frame beds or mushroom beds at any time and in more or less quantity, but I am convinced that the rich earth of the vegetable garden has no more to do with producing toadstools than has any other good soil, and old manure has far less to do with it than has fresh manure.
All practical gardeners know how apt hotbeds, in spring when their heat is on the decline, are to produce a number of toadstools; and, also, that when the bed is "spent," that is, when the heat is altogether gone, the tendency to bear toadstools has gone too. This peculiarity is more apparent in spring than in fall. All mushroom growers know that spurious fungi, when they appear at all, are most numerous three to two weeks before it is time for the mushrooms to come in sight. The same growth appears in the manure piles out in the yard; a few weeks after the strong heat of the manure has gone lots of toadstools may be observed on and about the heaps, but on the piles of well-rotted cold manure we seldom find toadstools at all.
The fresh, clean stable manure used in mushroom-growing is not apt to be charged with the spores of pernicious toadstools; their presence is always most marked in the case of mixed manures.
And there is a current idea that mushrooms will not thrive in beds in which old manure abounds, either in the loam or fermenting material; that it kills the mycelium. This, too, I must refute. I have seen heavy crops of spontaneous mushrooms come up in violet and carnation beds in winter, and where the soil consisted of at least one-fourth of rotted manure well mixed with the earth. In cucumber and lettuce beds the same thing has taken place. And in similar beds that have been planted artificially with spawn, good crops of mushrooms have also been raised, and the mycelium, instead of evading the lumps of old manure in the soil often forms a white web right through them.
CHAPTER XIII.
EARTHING OVER THE BEDS.
This is an important operation in mushroom-growing, and the one for which loam is indispensable. It consists in covering the manure beds, after they have been spawned, with a coating, or casing as it is more commonly called, of loam. The spawn spreads in the manure and rises up into the casing, where most of the young mushrooms develop, and all find a firm foothold. The loam also contributes to their sustenance. And it protects the manure, hence the spawn, from sudden fluctuations of temperature, and preserves it from undue wetting or drying.
The best soil to use for this purpose is rich, fibrous, mellow loam, such as is described, page 100.
If the manure is fresh and in good condition and the beds are in a snug cellar or closed mushroom house, I would not case them until the second week after spawning, say about the eighth or tenth day; but were these same beds in an open, airy shed or other building I would case them over some days earlier, say the fourth or fifth day. A fear is often expressed that when beds are cased within three or four days after being spawned the close exclusion of the manure from the air is apt to raise the heat of the manure in the bed, and thereby destroy the spawn; but I have never known of any truth in this theory, and with well-prepared manure I am satisfied no brisk reheating takes place, at least the thermometer does not indicate it. The great danger of early casing is in killing the spawn by burying it too deep in damp material and before it has begun to run through the manure.
I have conducted several experiments in order to satisfy myself regarding when is the proper time to case the beds, and have found no difference in results between beds that were cased over as soon as they were spawned and others that were not cased over until the fourth, seventh, tenth, or fourteenth day after spawning. The good or bad results in the time of casing depend on the condition of the manure in the beds, the depth at which the spawn has been inserted, the openness or closeness of the place in which the beds are situated, and other cultural conditions. But to delay casing as late as the fifteenth or sixteenth day after spawning is injurious to the crop, because in applying the covering of soil we are sure to break many of the mycelium threads that have by this time so freely permeated the surface of the manure. After the fourth week little white knots may be observed here and there on the spawn threads; these are forming mushrooms, and to delay casing the bed until this time would smother these little pinheads, and greatly mar our prospects of a good crop.
Peter Henderson, in his invaluable work, "Gardening for Profit," has given rise to a deep seated prejudice against molding over mushroom beds as soon as they are spawned by telling us that in his first attempt at mushroom-growing he had labored for two years without being able to produce a single mushroom, and all because he molded over his beds with a two-inch casing of loam just as soon as he had spawned them. Then he changed his tactics, and did not mold over the beds until the tenth or twelfth day after spawning, and was rewarded with good crops of mushrooms. Now, notwithstanding Mr. Henderson's experience, it is a fact that many excellent growers spawn and mold their beds the same day, and with success. But Mr. H. has done much good in displaying a rock against which many might be wrecked, so much depends upon other cultural conditions. The old practice of inserting the spawn three or more inches deep into the manure bed and then molding it at once with two inches deep of loam was enough to destroy the most potent spawn; nowadays we barely cover the spawn with the manure, and this is how molding over at once is so successful.
All the preparation necessary is to have the loam in medium dry, mellow condition, well broken up with the spade or digging fork, and freed from sticks, stones, big roots, clods, chunks of old manure, and the like.
Sifting the soil for casing the beds is labor lost. Sifted soil has no advantage over unsifted earth, except when it is to be used for topdressing the bearing beds or filling up the holes in their surface.
The condition of the soil should be mellow but inclined to moist. If wet it can only be used clumsily and spread with difficulty; if dry it can be spread easily but not made firm, and on ridge beds can not be put on evenly. But when moderately moist it can be spread easily and evenly on flat or rounded surfaces, and made firm and smooth.
How deep the mold shall be put upon the bed is also an unsettled question. Some growers recommend three-fourths of an inch, others one, one and one-half, two, or two and one-half inches, and some of our best growers of fifty or seventy-five years ago were emphatic in asserting three inches as the proper depth, but among recent writers I do not find any who go beyond two and one-half inches. My own experience is in favor of a heavy covering, say one and one-half to two inches. In the case of a thin covering the mushrooms come up all right but their texture is not as solid as it is in the case of a heavy covering, nor do the beds continue as long in bearing; besides, "fogging off" is much more prevalent under thinly covered than under heavily covered beds; also, when the coating of loam is heavy a great many more of the "pinheads" develop into full sized mushrooms than in the case of thinly molded beds.
Opinions differ as to firming the soil. I am in favor of packing the soil quite firm, and have never seen good mushrooms that could not come through a well firmed casing of loam, and I never knew of an instance where firm casing stopped or checked the spreading of the mycelium or the development of the mushrooms. In the case of flat beds,—for instance, those made on shelves and floors,—a slightly compacted coating (and this is all Mr. J. G. Gardner uses) may be all right, but in the case of alongside-of-walls, ridge, and other rounded beds I much prefer and always use solidly compacted casings.
Mr. Henshaw has for several years used green sods about two inches thick, put all over the bed, grass side down, and beaten firmly. The advantage of using sods instead of soil, he thinks, is that the young clusters of mushrooms never damp or "fogg off" as they are apt to do when soil is used.
I have given this green sods method repeated and careful trials, and am satisfied that it has no advantages, in any way, over common fibrous loam; indeed, it is not as good. No matter how firmly a sod, having its green side down, may be beaten on to a bed of manure, there is barely any union between the two; the sod merely rests upon the dung, but so closely that the mycelium enters it freely. A slight movement or displacement of the sod after the spawn enters it will break the threads of mycelium between the manure and the sod, and this will destroy the immature mushrooms forming in the sod. This gave me a good deal of trouble. Stepping on the sod would disturb it. A clump of strong mushrooms formed under it sometimes displaces it in forcing their way to the surface.
Sods are only fit for use on flat beds where they can lie solid; on rounded or ridge beds they are too liable to be disturbed. And the trouble and expense of procuring sods are too great to warrant their use, even if they had any advantages.
CHAPTER XIV.
TOPDRESSING WITH LOAM.
In beds that are in full bearing or a little past their best we often find multitudes of very small or what we call "pinhead" mushrooms, that seem to be sitting right on the top of the loam, or clumps that have been raised a little above the surface by growing in bunches, or what we term "rocks"; now a topdressing of finely sifted fresh loam, about one-fourth to one-half inch thick, spread all over the bed, will help these mushrooms materially without doing any of them harm. But while this topdressing assists all mushrooms that are visible above ground, no matter how small they may be when the dressing is applied, I am not convinced that it induces greater fertility in the spawn, or, in other words, induces the spawn to spread further and produce more mushrooms than it would were no topdressing applied. I know that this is contrary to the opinions and writings of many, at the same time it is according to my own observation.
Go over the bed very carefully and pick out every soft or "fogged-off" mushroom, no matter how small it may be, and root out every bit of old mushroom stem or tough spongy material formed by it, and in this way get the bed thoroughly cleaned. Then fill up all the holes caused by pulling the mushrooms or rooting out the old stumps, and when the whole surface is level apply the topdressing evenly all over the face of the bed, avoiding, as much as possible, burying the well advanced mushrooms. While it would be very well to pack the dressing smoothly over the bed, it is impracticable; we may press it gently with the back of the hand on the bare spots between the mushrooms, but we should not even do this over the mushrooms, no matter how tiny they may be, else many of the "pinheads" will be injured and cause "fogging off."
But we can firm the dressing to the bed by watering it, which may be done over the whole surface of the bed, and without sparing the mushrooms, large or small. Use clear water and apply it gently through a water-pot rose. I always do this, and have never known it to injure the young mushrooms.
In the case of mushroom beds in which black spot has appeared in the crop, I have found that a topdressing of fine, fresh earth applied evenly all over the bed acts, to a certain extent, as a preventive of further attack, but of course has no effect upon any of the already affected mushrooms, large or small.
CHAPTER XV.
THE PROPER TEMPERATURE.
The best temperature at which to keep the mushroom house or cellar is 55° to 57°. But much depends upon the method of growing the esculent; the construction of the house or cellar, and other circumstances. Mushrooms can be successfully grown in buildings in which the temperature may be as low as 20° or as high as 65°. By covering the beds well with hay or other protecting material they can be kept warm, even in sharp frosty weather, as the London market gardeners do with their outdoor beds in winter; but when the temperature in the structure in which the mushrooms are grown averages as high as 70° we can not hope for success; indeed, 65° is too high.
A high temperature in a close house or cellar is injurious; it hurries in the crop and forces up the mushrooms weak and thin-fleshed and with ungainly, long stems; it soon exhausts the bed. The time when its evil effects are least visible is early in the fall and late in spring when the outside temperature is high, and when the beds are in somewhat airy rather than close quarters. In the Dosoris cellars there is a steady difference of about 5° in the temperature between the end next the boiler, which is kept at 60° precisely, and that of the farther end, which registers 55° steadily. There is very little difference in the weight of crop produced on the beds at either end of these cellars, but what little there is is in favor of the cooler end. At 60° the crop begins to come in in six to seven weeks after spawning, lasts for three to four weeks in heavy bearing and a week or more longer in light bearing, and then it gradually dwindles.
In a temperature of 55° it may be seven weeks after spawning before the mushrooms appear. In a temperature of 50° they may take a few days longer in appearing, but, as a rule, they are firm, heavy, short-stemmed, and perhaps a little furry on top and clammy to the touch, and the beds last in good bearing for two months; indeed, often a whole winter long. But I have failed to find that the whole crop from a bed in a 45° to 50° temperature was any greater than that of a like bed in a 55° to 57° temperature; it is merely a case of getting in six weeks from the warmer house what it takes ten weeks to get from the cooler one.
In a temperature of 50° it is not necessary to cover the beds to increase their warmth, nor is it needful even in one of 45°, if there is a fair warmth in the body of the bed to keep the spawn working; but if the warmth of the interior of the bed falls under 57°, and the atmospheric temperature under 45°, the bed should be kept warm by covering with hay, straw, matting, or other material, or better still by boxing it over and laying this covering on the outside of the boxing. When cold thicken the covering, when warm lessen it.
CHAPTER XVI.
WATERING MUSHROOM BEDS.
If the beds get dry they should be watered, for mushrooms will not grow well in dry beds or in a dry atmosphere. Watering is an operation requiring much care. In properly-made beds the manure should remain moist enough from first to last, and whatever dryness is evident should be in the loam casing of the beds and the atmosphere. In all artificially heated mushroom houses the beds and atmosphere are apt to get too dry at one time or another; in underground houses or cellars this is less apparent than in above-ground structures; in shaded north-facing houses dryness is less troublesome than in houses more openly placed.
Endeavor by all fair means to lessen the necessity for watering the beds, but when water is needed never hesitate to give it freely. Mulching the beds and maintaining a moist atmosphere are the best preventives. After the beds are spawned and molded it is a good plan to cover them with a light coating of strawy litter or hay to prevent drying, but this mulching should be removed when it is near time for the young mushrooms to appear. A light sprinkling of water over this mulching every few days, but never enough to reach the soil, assists in preserving enough moisture in the bed under the mulch and also in the atmosphere of the house.
Clean, soft water at a temperature of 80° or 90°; a little warmer or a little colder will not hurt, but do not use water higher than 110°, as it might injure the little pinheads, nor lower than the average temperature of the house, as it would chill the bed, and this should always be avoided.
Use a small or medium-sized watering pot with a long spout and a fine rose sprinkler. Apply the water in a gentle shower over the bed, mushrooms and all, but never use enough to allow it to settle in pools or run off in little streams. Clean water sprinkled over the mushrooms does not appear to hurt them, but they should never be touched with manure water, as it stains them. Just as soon as the surface of the bed shows signs of dryness give it water, the quantity depending upon the condition of the bed. Never let a bed get very dry before watering it. To thoroughly moisten a very dry bed requires a heavy watering; so much, indeed, that the sudden change might injuriously affect the young mushrooms and spawn. Give enough water at a time to moderately moisten the soil, not to soak it, but never sufficient to pass through the soil into the manure. Clean water only should be used until the beds come into bearing, but after that time manure water may be employed with advantage; however, this is not at all imperative; indeed, excellent crops can be and are continually being produced without the aid of manure water at all.
In the case of beds in full bearing, manure water is beneficial to the crop. Apply it from a small watering pot with a long narrow spout but no rose, and pour the liquid on gently over the surface of the bed, running it freely between the clumps but never touching any of the mushrooms. For this reason a rose should not be used.
I have always used manure water for mushrooms more or less, but during the past two seasons—'87-'88 and '88-'89—I have experimented with it continuously and very carefully, using it in some form or other on part of every bed, and am satisfied that manure water made from fresh horse droppings is the best, and the dark colored liquid, the drainings from manure piles, is the poorest; in fact, this latter is not as good as plain water, for it seems to have a deadening rather than quickening effect upon the beds. Cow manure and sheep manure make a good liquid manure, but still I prefer the horse manure, and although having given hen and pigeon manure and guano fair tests I am not satisfied that they have benefited the crop, and there is always a risk in their use. Liquid manure made from the contents of the barnyard tank has not done much good, but fresh urine from the horse and cow stables diluted twelve to fifteen times its bulk has given favorable results.
Mushrooms not only bear with impunity but appear to enjoy a stronger liquid manure more than do any other cultivated plants, and I am satisfied that the weak liquids usually recommended for pot and garden plants would be barely more efficacious than plain water for mushrooms.
The manure water that has given me most satisfaction is prepared as follows: Dump two bushels of fresh horse droppings into a forty-five gallon barrel and fill up with water; stir it up well and let it settle over night. Drain off the liquid the next day and add a pound of saltpeter to it. For use, to a pailful of this liquid add a pailful of warm water. Water of about 80° to 90° is best for mushroom beds. Saltpeter is an excellent fertilizer for mushrooms. I use it in two ways, namely: First, powdered and mixed in the soil for casing the beds, at the rate of two ounces of saltpeter to the bushel of earth. Second, dissolved in water at the rate of two ounces of saltpeter to eight gallons of water, and sprinkled over the beds.
Common salt I use as an insecticide and also as a fertilizer, and am satisfied that it proves beneficial in both ways. Sometimes I sprinkle it broadcast on the surface of the beds, always on the bare places, never touching the mushrooms, and leave it there for a day or two, then with a fine, gentle sprinkling of water wash it into the soil. This is to help destroy the anguillulæ. As a fertilizer only dissolve four ounces of salt in ten gallons of water, and with this sprinkle the beds.
A too dry atmosphere can be remedied by sprinkling the floors, walls, or litter coverings on the beds with water, not heavily or copiously, but gently and only enough to wet the surfaces; better moisten in this way frequently than drench the place at any one time. But I very much dislike sprinkling the beds in order to moisten the atmosphere. An experienced man can tell in a moment whether or not the atmosphere of the mushroom house is too dry. The air in the mushroom house should always feel moist, at the same time not raw or chilly, and the floor and wall surfaces should present a slow tendency to dry up, and the earth on the beds should retain its dark, moist appearance. The least tendency to dryness should at once be relieved by damping the wall and floor surfaces.
In houses heated by smoke flues, or still more by ordinary stoves and sheet iron pipes, it may be necessary to dampen the floors and walls once or several times a day to maintain a sufficiently moist atmosphere, but where hot water pipes are used and the houses are tight enough to require but little artificial heat, such frequent sprinkling will not be necessary. In the case of beds in unheated structures the ordinary atmosphere is generally moist enough.
Manure Steam for Moistening the Atmosphere.—The late James Barnes, of England, a grand old gardener, writing in the London Garden, Vol. III, page 486, describes his method of growing mushrooms sixty years ago, and says: "In winter a nice moist heat was maintained by placing hot stable manure inside, and often turning it over." Mr. John G. Gardner, of Jobstown, N. J., is one of Mr. Barnes's old pupils and a most successful mushroom grower, and he now practices this same method of moistening the atmosphere by hot manure steam. See page 21.
In damping the floors of the mushroom house, as well as the beds, I use a medium-sized watering pot and fine rose; but in sprinkling the walls and other parts not readily accessible by the watering pot I use a common garden syringe.
CHAPTER XVII.
GATHERING AND MARKETING MUSHROOMS.
This is an important point in the cultivation of this esculent, and should be attended to with painstaking discretion.
When mushrooms are fit to pick depends upon several conditions; for instance, whether for market or for home use, and if for the latter, whether they are wanted for soups or stews. For fresh and attractive appearance and best appreciation in the market, pick them when they are plump and fresh and just before the frill connecting the cap with the stem breaks apart. The French mushrooms should always be gathered before the frill bursts; the English mushrooms also look best when gathered at this time, but they are admissible if gathered when the frill begins to burst and before the cap has opened out flat. If the mushrooms display a tendency to produce long stems pick them somewhat earlier, soon enough to get them with short shanks, for long stems are disliked in market; so, too, are dark or discolored or old mushrooms of any sort. Sometimes we may not have enough mushrooms ready at one gathering to make it worth while sending them to market, and are tempted to let them stay ungathered until to-morrow, when they have grown larger and many more shall have grown big enough to gather. This should never be done. It will give an unfavored, unequal lot, some big, some little, some old, some young. Far better pick every one the moment it is ready to gather, and keep all safe in a cool place and covered until some more are ready for use, and in this way have a uniform appearing lot of young produce.
Mushrooms for soups should always be gathered before they burst their gills; indeed, they are mostly gathered when in a button state; that is, when they are about the size of marbles. In this condition, when cooked, they retain their white appearance and do not discolor the soup. Immature mushrooms are deficient in flavor.
For home use, for baking, stewing, broiling, or for cooking in any way in which the tenderness of the flesh and the delicious aroma of the mushrooms are desirable in their finest condition, let the mushrooms attain their full size and burst their frills, as seen in Fig. 24, and gather them before the caps open out flat, or the gills lose any of their bright pink color. If you let them get old enough for the gills to turn brown before gathering, the mushrooms will become leathery in texture, and lose in flavor and darken sadly in cooking.
In picking, always pull the mushrooms out by the root, and never, if practicable to avoid it, cut them over with a knife. In gathering, take hold of the mushrooms and give them a sharp but gentle twist, pressing them down at the same time, and they generally part from the bed without any trouble; then place them in the baskets, root-end down, so as to keep them perfectly clean and free from grit. Sometimes when several mushrooms are joined together in one root-stock and it is impossible to remove one without disturbing the whole, cut it over rather than pull it out. In the case of clumps of young mushrooms, where one can not be pulled out without displacing some of the others also, cut it out rather than pull it. There is a knack in pulling mushrooms, easily attained by practice. And even when they come up in thick bunches and it would appear impossible to pull out the full-grown ones without disturbing the others, a practiced hand will give them a twitch and a pull—they often part from the bed by the gentlest touch—and get them out without unfastening any of the multitude of small buttons that may be growing around them.
The advantages of pulling over cutting are several: It benefits the bed. If we cut over a mushroom and leave its stump in the ground, in a few days decay sets in and a fluffy or spongy substance grows around the old butt, which destroys many of the little mushrooms around it, as well as every thread of mycelium that comes in contact with it. One should be particular to scoop out these stumps with a knife before this condition takes place, and go over the beds every few days to fill up the holes, made in scooping out the old stumps, with fresh loam.
Pulled mushrooms always keep fresh longer than do those that have been cut. In the interest of the market grower they have another advantage. Mushrooms are bought and sold by weight, and as the stems are always retained to the caps all are weighed together; if part of the stems had been cut off the weight would have been reduced, and, in like proportion, the price; but if the stems are retained entire not only are the mushrooms benefited, but the weight, and with it the price, is also increased.
Gathering Field or Wild Mushrooms.—Go in search of them in the morning before the sunshine gets warm and they become too open or old. If you wish to gather and preserve them in their most perfect condition pull them up by the "roots," carefully remove any soil from them, and then lay them orderly in the basket, the root end down; and by spreading a stout sheet of paper over the layer, another may be arranged above it in the same way, and so on until the basket is full. But if you are not so particular and wish them for immediate use, or for ketchup or drying, the common way of cutting them off and carrying them home in bulk will answer well enough.
Marketing Mushrooms.—Most market growers who live immediately around New York City sell direct, and deliver their mushrooms to hotels, restaurants, and fancy fruiterers. But some of them, also most of those who live at a considerable distance from the city, sell their mushrooms through commission merchants in New York; they, in turn, sell in quantities to suit customers.
Mushrooms are sold by the pound, and come into market in boxes made of strong undressed paper. Some growers have light wooden boxes made that hold from one to four pounds of mushrooms each, and these make convenient and strong packages for shipping by express. They may be sent singly, or, as is the case with the paper boxes, several packed together in crates or boxes. In sending directly to hotels, cheap baskets, holding one or several pounds—Mr. Gardner's baskets hold twelve pounds—are often used, but in sending to commission merchants, who have to deal them out in quantities to suit customers, mushrooms should always be packed in one, two, three or four pound boxes or baskets, preferably one pound. Mushrooms are not like potatoes or apples, that can be handled, remeasured, and repacked without damaging them. Each rehandling will certainly discolor and perhaps break a good many of them, rendering them unsalable, if not worthless.
The utmost care in gathering and packing of mushrooms for shipping is of primary importance. Gather them the moment they are in best condition, no matter whether or not they are to be packed and shipped the same day; never let them blow open before gathering them; and never cut off short stems. Long stems have to be shortened, but not until everything is ready to pack them. With a very soft hair brush dust off any earth that may stick to the cap of the mushroom, and with a harder brush or the back of a knife rub the earth off of the root end of the stem. Then sort the mushrooms,—the big ones by themselves, the middle-sized by themselves, the small or button-sized ones by themselves, and pack each kind by itself. Pack very firmly without bruising, and so as to show the pretty caps to the best advantage. Never pack mushrooms more than two deep without using plenty of soft paper between the layers, and never put a heavy bulk of them into one box or basket. They discolor so easily that, all things considered, about a pound is enough in a box, if we wish them to carry safely and retain their bright, fresh skin without tarnishing.
Mr. Barter, of London, writes me: "The punnets we use for marketing our mushrooms in are the same that are used for strawberries or peaches. These hold just one pound, but it is becoming more customary now to have little boxes made holding from three to five pounds, as these are better for packing in larger cases for long journeys."
CHAPTER XVIII.
RE-INVIGORATING OLD BEDS.
There is a wide-spread impression among horticulturists that worn out beds which have ceased to bear may, by means of watering and certain stimulants and warming up again, be so re-invigorated as to start into full bearing, and yield a second and a good crop. I have given this question much painstaking and practical consideration, and have absolutely failed to revive a "dead" bed. I have not been able to do it myself, and any instance of its having been done has never come under my observation. This may appear heresy anent the multitudinous writings to the contrary.
A mushroom bed may keep on bearing in a desultory way for many months, and now and again show spurts of increased fertility; but this is no second crop; it is merely a prolonged dribbling of the first crop. A bed, by reason of cold or dryness, may, as it were, stand still or partially stop bearing, and soon after it is remoistened, warmed, and otherwise submitted to congenial conditions, will display renewed energy; but this is no second crop; it is merely a spurt of the first crop caused by extra favorable cultural conditions. But to show how vaguely this question which is so much written about is regarded, let me quote from a letter to me by Mr. J. Barter, who grows 21,000 lbs of mushrooms a year for the London market: "You ask me, 'Do you ever get a second crop?' My beds last in bearing, on an average, each three months, and that I reckon to be three crops. But whether it be three or six months, the weight of mushrooms is about the same. As there is in, say a ton of manure, only so much mushroom-producing power, if you force it to produce that weight in two months you are a gainer, as you thereby save in labor; but when that producing-power is exhausted it will produce no more mushrooms."
A spent mushroom bed is one that has been kept in bearing condition under the most favorable circumstances at our command, and it has borne a good crop, lasted some two months in bearing, and now it has stopped bearing (except in a meagerly, desultory way) because the spawn or mycelium has exhausted itself and is dead. Then, without living spawn in the bed how are we to get mushrooms? Some bits of mycelium are still alive and yield the desultory few, but every mushroom that they yield is preying on their vitality, and after a time they too shall die and the bed be completely barren, for the mycelium is altogether dead, and without mycelium mushrooms are an impossibility. We can keep mushroom mycelium in active growth the year round, and year after year, providing we never let it bear mushrooms. This is done by taking the mycelium, just before it begins bearing, from one manure bed and plant it in another, and so on from bed to bed. At every fresh transplanting the mycelium exerts itself into renewed growth, for it must become a strong plant before it has strength enough to produce and support a mushroom. Our utmost efforts have never rendered mycelium in a mushroom-bearing condition perennial.
CHAPTER XIX.
INSECT AND OTHER ENEMIES.
The mushroom grower has his full share of insects to contend with, and in order to overcome them one should acquaint himself with them, and know what they are, what they do, whence they came, and how to destroy them. One should study the diseases and mishaps of his crop and endeavor to know their cause. If we know the cause of failing health in plants, even in mushrooms, we can probably stop or devise a remedy for the disease or means to prevent its recurrence, and if we can not benefit the present subject we are forewarned against future attacks. But there is a deal of mysterious trouble in this direction in mushroom-growing. We are likely to know something about the depredations committed by insects or parasitic molds above ground, but I am sure there is a good deal of mischief going on under ground of which we know very little, if anything. The ills to which the mycelium is subject are not at all fully understood.
"Maggots."—This is the common name among practical mushroom growers for the larvæ of a species of fly (Diptera) which from April on through the warm summer months renders mushroom-growing unprofitable. It is unavoidable, and so far has proved invincible. It attacks the mushrooms in deep cellars, above-ground houses, greenhouses, or frames, and is often quite common in early appearing crops in the open fields. We sometimes read that it does not occur in unheated cellars, but this is a mistake, for in our unheated tunnel cellars, where the temperature in April does not exceed 55°, maggots always appear about the end of this month. But it is true that in the case of cool houses and where the beds are covered over with hay or straw maggots do not appear as early in the season as they do in warm houses and open beds. While rigid cleanliness, and care in keeping the house or cellar closed, no doubt have much to do in lessening the trouble, I have never been able to overcome it, and know of no one who has. We simply stop growing mushrooms in summer.
The maggots or larvæ are about three-sixteenths to four-sixteenths of an inch long, white with black head, and appear in all parts of the mushroom, but mostly in the cap and at the base of the stem, and perforate hither and thither leaving behind them a disgusting network of burrows. The tiny buttons, about as soon as they appear at the surface of the ground, are infested, but this does not check their growth, and when they become mushrooms large enough for gathering, unless it be for a dark looking puncture or tracing now and then visible on the outside of the caps and stems, there are but few signs to indicate to the inexperienced eye the presence of maggots. And this is why maggoty mushrooms are so often found exposed for sale in summer. But in large or full-grown mushrooms, and especially the white-skinned varieties, their presence is visible enough. Although very repugnant, however, and utterly unfit for food, maggoty mushrooms are not poisonous.
But all the mushrooms of summer crops are not maggoty, only a large proportion of them; the evil begins in April, and increases as the summer advances, until August, when it decreases, and in October completely stops—at least this is my experience.
A solution of salt, saltpeter, or ammonia sprinkled over the surface of the beds does not, in this case, do any good as an insecticide, pyrethrum powder diffused through the atmosphere, and tobacco smoke, have been ineffectual. Burning a lamp set in a basin of water with a little kerosene floating on the surface is a most doubtful operation. Multitudes of flies are destroyed by this lamp trap, but they are the poor little innocent "manure flies," and the atmosphere of the house is vitiated and rendered unhealthy for the crop. I have tried these lamp traps season after season, and never knew of their doing any good; that is, the maggots seemed just as numerous in the lamp-trapped cellar as in the other cellar in which no lamp trap had been used.
Regarding this "maggots" question, Mr. J. F. Barter, of London, writes me: "During the summer months the outdoor mushrooms get maggoty before they are big enough to gather, but of course they can be grown in cool cellars all the year round.... I know of no sure cure for them (the maggots); of course a slight sprinkling of salt with manure or mold does prevent, to a certain extent, but it must be used very carefully." Now my experience is, as I have already said, that it is impossible to grow mushrooms here in summer, even in cool cellars, without having them more or less maggoty. As regards the salt and loam preventive, I have tried it lightly and heavily, but without any apparent good effect.
Black Spot.—All mushroom growers are familiar with this disease, but unless it appears in pronounced form very little notice is taken of it, even by market men, for we see spotted mushrooms continually exposed for sale. It appears as dark brown spots, streaks, or freckles, on the top of the mushroom caps, and increases in distinctness and breadth with age. Fig. 25. It is caused by eel worms (Anguillulæ). These minute creatures enter the mushrooms when the latter are in their tiniest pin form and before they emerge from the ground. If a button arises clean it remains clean, if diseased it continues to be diseased, and it is a fact that if one mushroom in a clump has black spot we usually find that every mushroom in the clump has it. But mushrooms growing from the same bit of spawn and that come up an inch or two away from the spotted ones may be perfectly clean. Black spot has never occurred with me in new beds, and seldom in those in vigorous bearing, but it generally appears in beds that have been in bearing condition for some weeks or are declining. It does not confine itself to any particular spot or part of the bed, and sometimes it is much more plentiful than at others. Between October and March we have very little black spot, but as the spring opens this disease increases. During the winter season, with careful attention, perhaps not so much as one per cent will show black spot, but as the warm weather sets in the per centage increases until in May, when as many as twenty per cent may be affected by it.