Mushroom Culture: Its Extension and Improvement

by W. Robinson

Everywhere on the surface of these little beds small mushrooms were peering forth in quantity; as the beds are regularly gathered from every day, no very large ones are seen. They are preferred when about the size of a chestnut, and are removed root and branch, a small portion of finely sifted earth being placed in each hole, so as to level the bed as in the caves at Montrouge. If the old superstition that a mushroom never grows after being seen by human eyes were true, the trade of a champignonniste would never answer here, as the little budding individuals come within view every day during the gathering and earthing operations. The most perfect cleanliness is observed everywhere in the neighbourhood of these beds, and the whole surface of each avenue is covered by them, leaving passages of ten inches or a foot between the beds. At the time of my visit (Sept. 29, 1868) the crops of the cultivator were reduced to their lowest ebb, and yet about 400 lbs. per day were sent to market. The average daily quantity from this cave is about 880 lbs., and sometimes that is nearly doubled.

In some parts of the cave the work of ripping out the stone by powder and simple machinery continually goes on. The arches follow the veining of the stone, so to speak; their lower parts are of hard stone, the upper ones of soft, except the very top, which is again hard. There is but a slight crust of stone above the apex of each arch, and above that the earth and trees.

It may be supposed that the profits from such an extensive culture are great; and so they are, but the expense is great also. The proprietor informed me that culture on a more limited scale than he pursued last year at Méry gave the best return in proportion to expense, the care and supervision required by so many miles of beds being too great.

All the manure employed is brought from Paris by rail, as the place is twenty-five miles from that city by road. In the first place, so much per month is paid in Paris for the manure of each horse; then it has to be carted to the railway station and loaded in the waggons; next it is brought to the station of Auvers, and afterwards carted a couple of miles to the quarries, paying a toll for a bridge over the Oise on the way. That surely is difficulty enough for a cultivator to begin with! Then it is placed in great flat heaps a yard deep by about thirty long and ten wide, not far removed from the mouth of the cave, and here it is prepared, turned over and well mixed three times, and as a rule watered twice. About five or six weeks are occupied in the preparation, long manure requiring more time than short. The watering is not usually done regularly over the mass, but chiefly where it is dry and overheated. Every day manure is brought from Paris; every day new beds are made and old ones cleared out—the spent manure being used for garden purposes, particularly in surfacing or mulching, so as to prevent over-radiation from the ground in summer. The chief advantage the cultivator here has is the facility of taking his manure or anything else in or out in carts, as easily as if the beds were made in the open air. Near Paris, on the contrary, everything has to be sent up and down through shafts like those of an old well, and the men have to creep up and down a rough pole like mice. Many men are employed in the culture, the daily examination of sixteen miles of beds being a considerable item in itself. Here and there a barrier in the form of straw nailed between laths may be seen blocking up the great arch to a height of six feet or so. This is to prevent currents of air wandering about through the vast passages.

The mode of preparing the spawn here is entirely different to ours. They prefer virgin spawn—that is to say, spawn found naturally in a heap of manure. But as this material cannot be obtained in sufficient quantity to meet the wants of such extensive growers, they put a small portion of it into a mushroom-bed to spread, and instead of allowing this bed to produce mushrooms, it is all used as spawn, and is valued more than any other. Of course abundance of spawn occurs in the old beds, but it is never used directly. It is, however, frequently employed to spawn a small bed when virgin spawn cannot be obtained. In this case the small bed devoted to the propagation of spawn is placed in the open air, and covered with straw, and as soon as it is permeated with the spawn it is carried into the caves and used. As the making and spawning of beds is a process continually going on, a bed of this sort must be ready at all times. It is never made into bricks as with us, but simply spread through short, partly-decomposed, manure.[A]

[ [A] Mr. Speed, superintendent of the gardens at Chatsworth, has recently prepared his own spawn, as described on [p. 73], and with perfect success.

I was informed that coal-mines are not adapted for growing mushrooms, and the smallest particle of iron in the beds of manure is avoided by the spawn, a circle around it remaining inert. It is said to be the same with coal. If an evil-disposed workman wishes to injure his employer, he has only to slip along by the beds with a pocketful of rusty old nails, and insert one here and there.

The beds remain in good bearing generally about two months, but sometimes last twice and three times as long. A useful contrivance for facilitating the watering of the beds has lately been invented; it consists of a portable water-cistern to be strapped to the back and fitted with a rose and tubing, so that a workman may carry a larger quantity of water, and apply it more regularly and gently than with the old-fashioned watering-pots—while one hand is left free to carry the lamp. An iron frame has also been invented, in which the bed is first compressed and shaped, the frame being then reversed and the bed placed in position. Another invention for earthing the beds over as soon as the spawn has taken will soon be in operation if not already so. As on an average 2500 yards of beds are made every month, simple mechanical contrivances to facilitate the operation will prove of the greatest advantage to the cultivator.