Our Edible Toadstools and Mushrooms and How to Distinguish Them / A Selection of Thirty Native Food Varieties Easily Recognizable by their Marked Individualities, with Simple Rules for the Identification of Poisonous Species

by W. Hamilton Gibson

MEADOW MUSHROOM

Agaricus campestris

"The" mushroom

Description of Campestris

Perhaps the one species which enjoys the widest range of popular confidence as the "mushroom" in the lay mind, as distinguished from "toadstool," is the Agaricus campestris, known as the "meadow mushroom" (Plate 5). It is the species commonly exposed in our markets. Its cultivation is an important industry, but it often yields an enormous spontaneous harvest in its native haunts. The plate shows a cluster of the mushrooms in their various stages of development, the detached specimen below representing the semi-opened condition in which the fungus is usually gathered for market. It will be observed that the base of the stem is entirely free from any suggestion of a volva or cup. As its popular name implies, this species in its wild state is one of the voluntary tributes of our late summer and autumn meadows and pastures, though it may occasionally frequent lawns, shrubberies, and barn-yards. In size it varies from two to three and a half inches across the pileus or cap, which is either smooth or slightly rough, scaly, or scurfy, and creamy white or tawny in color, according to age or variety. The most important distinguishing feature of this species is the color of the gills. If we break away the "veil" in the unopened specimen, we find them to be of a pallid flesh tint. In the more advanced state they become decidedly pinkish, with age and expansion gradually deepening to purplish, purple-brown, and finally brownish black. The gills are of unequal lengths, as shown in the section. The stem is creamy white and of solid substance, and always shows the remains of the veil in a persistent frill or ring just beneath the cap.

PLATE V
"THE MUSHROOM"

Agaricus campestris

Pileus: At first globular, its edge connected to stem by the veil; then round convex, at length becoming possibly almost flat. Surface dry, downy, or even quite scaly, varying in color from creamy white to light brown. Diameter at full expansion, about three inches.

Gills: Unequal in length; pink when first revealed, becoming brownish, brown, purplish, and finally almost black.

Stem: Solid; of the color of the cap; paler and white in section, retaining the remnant of the veil in a permanent ragged ring.

Spores: Brown.

Taste: Sweet and inviting, and odor agreeable.

Habitat: Pastures, lawns, and open rich soil generally.

Season: Late summer and early autumn, occasionally in spring.

PLATE V

Agaricus Campestris.

Cultivation of mushrooms

Doubtless a sufficient and satisfactory reason for the universal dignity which this species has acquired as "the mushroom" may be found in the fact that it is the only species prominently under cultivation, and almost the only one which is sure to respond to the artificial cultivation of its spawn in the so-called "mushroom bed." The "spawn" of the Campestris has thus become a mercantile commodity, duly advertised in the seedsmen's catalogues.

Mushroom "spawn" bed

This so-called spawn is in truth nothing but the mycelium, or subterranean vine of the mushroom (see [Plate 2]), taken from the beds in which the mushrooms have been grown, or in which the mycelium has been cultivated. The cultivator simply prepares a "bed" to receive it—duplicating as far as possible the soil conditions from which it was taken, whether from foreign cultivation or his old manure-bed or stable-yard—a rich, warm compost of loam and horse-manure, this latter ingredient being a most important consideration, as the fungus in its several varieties, notably the larger, Agaricus arvensis, known as the "horse-mushroom," has followed the track of the horse around the world. These natural conditions having been even approximately fulfilled, will, within two months, generally reward the cultivator with a crop of mushrooms, which, with the continued ramifications of the mycelium permeating the muck as the yeast fungus permeates the home-made loaf, will insure a continual succession of crops for weeks or months, to be renewed spontaneously, perhaps, the following season.

The present volume, having specific reference to fungi in their wild state, and the celebration of their esculent virtues, being thus essentially in antithesis to artificial culture, further consideration of the cultivation of the mushroom is omitted. The reader is referred to the volumes in my bibliographical list, Nos. 8 and 22, in which full instructions will be found.

Species opposed to cultivation

Certain exceptions

The Campestris is conspicuous among mushrooms in its ready accommodation to artificial imitation of its native environment. There is no other mushroom which is thus confidently to be relied on. Other species—not a dozen, however, out of the thousands—will occasionally reward the cultivator, who has devoted the most scrupulous care to the humoring of their fastidious conditions of growth. Thus the Agaricus candicans of the Italian markets is said to have been successfully raised from chips of the white poplar which have been properly covered with manure. Other species, it is claimed, can be humored from a block of the cob-nut tree after singeing its surface over burned straw, while Dr. Thore claims that both Boletus edulis, and Agaricus procerus are "constantly raised by the inhabitants of his district from a watery infusion of said plants poured upon the ground." The truth of these statements has been denied by authorities, and individual experiment will only tend to discredit their trustworthiness. In general the mushroom or toadstool absolutely refuses to be "coaxed or cajoled." The mycelium of all is practically identical; but species such as the Coprinus, for instance, which are perhaps found growing naturally in company with the Campestris, and whose spawn is similarly transplanted to the artificial environment, will show no sign of reappearance, while its fellow may literally crowd the bed.

Not to be humored

The "fairy-ring" mushroom grows year after year upon our lawn, because its mycelium is continually present, simply threading its way outwardly, inch by inch, in the congenial surrounding soil. Instances are reported of the occasional successful establishment of this mushroom in new quarters by the transfer of a clod of earth threaded with mycelium taken from the "fairy-ring" to another lawn, in which the immediate soil conditions happened to be harmonious, and this method of actual transference of the spawn might occasionally be effectual. But the writer, in his limited number of experiments, has never yet been able to propagate a mushroom by a transfer of the spores to soil where the conditions would appear to be exactly suitable. On a certain lawn, for instance, every year I obtain a number of the Coprinus comatus ([Plate 16]). Upon another lawn, apparently exactly similar as to soil conditions, I transfer the melting mushroom where it sheds its inky spore-solution upon the earth, and yet, after years of waiting, there is no response. Even an absolute transfer of the webby spawn from the original haunt has proven equally without result. Thus while the habitual fungus-hunter comes to recognize a certain logical association between a given character of natural haunt and some certain species of fungi—a prophetic suspicion often immediately fulfilled—as when he inwardly remarks, as he comes upon an open, clear spot in the woods, "This is an ideal haunt for the green Russula," and instantly stumbles upon his specimen; yet he may take the pallid spawn, with a small clod of earth from its roots, and place it in the mould not ten feet distant, apparently in identically auspicious conditions, and it absolutely refuses to be humored. He may mark the spot, and look in vain in its precincts for a decade for his Russula, though the ground in the vicinity be dotted with them.

Dormant spores

Year after year I have thrown my refuse specimens of hundreds of species of fungi out of my studio window, over the piazza rail or upon my lawn, yet never with the slightest sign that one of the millions of spores in the species thus sown has vegetated.

Considering the ready accommodation of the Campestris, the contrast of the fastidiousness in other species is a notable phenomenon. As a rule, "they will not colonize; they will not emigrate; they will not be cheated out of their natural possessions: they refuse to be educated, and stand themselves upon their single leg, as the most independent and contrary growth with which man has to deal."

Plate VI. VARIATIONS IN AGARICUS CAMPESTRIS

Varieties of the Campestris

The Campestris is probably the most protean of all mushrooms, and mycologists are even yet at odds as to the proper botanical disposition of many of the contrasting varieties which it assumes. A few of these are indicated in Plate 6. Indeed, some of these, as in the Agaricus arvensis, following, have until quite recently figured as distinct species. In its extreme form it might well so do, but when science is confronted with an intermediate specimen bearing equal affinities to the Campestris and Arvensis—and perhaps reinforced by other individuals which actually merge completely into the Campestris—the discrimination of the Arvensis as a distinct species becomes impossible, and would hardly seem warrantable.

Berkeley gives the following selection of the more distinct varieties, not including the Arvensis with its variations, and which he considers a distinct species:

1. The so-called "garden mushroom," with its brownish, hairy, scaly cap.

2. A. pratensis, in which the pileus is more or less covered with reddish scales, and the flesh as well as gills a pinkish tinge.

3. A. villaticus, large size and very scaly.

4. A. silvicola, pileus smooth and shining, stem elongated and conspicuously swollen at base; often found in woods.

5. A. vaporarius, brown pilose coat which covers the stem as well as the cap, and leaves streaky fragments on the stalk as it elongates.

6. He also figures another marked form, with the cap of a reddish color, completely covered with a pilose coat; the gills being perfectly white in young specimens, and the flesh turning bright red when bruised.

Any one of the above, he admits, are as much entitled to classification as "distinct species" as the Arvensis.

The "horse" mushroom

The application of the title "horse-mushroom" to this last-mentioned species was generally supposed to be referable to the same popular traditions of which we see the analogies in the names horse-weed, horse-nettle, horse-balm, horseradish among the herbs—the prefix "horse" referring to the element of coarseness or rank growth. But in the instance of the mushroom it bears a deeper significance, as this ample cosmopolitan variety of the Campestris, which follows the horse all over the world, from stable and through lane to pasture, and which can only be grown in the manure of this animal, is now generally believed to be a secondary, exaggerated form consequent upon the following conditions:

The spores of the Campestris are shed in myriads in the pastures. The grazing horse no doubt swallows thousands of them, which, upon their return to the soil under especially favorable conditions for growth, vegetate into mycelium, and at length fructify in the full-formed mushroom. The dense white spawn of this species may often be seen beneath the manure in pastures where no sign of the mushroom itself is yet apparent.

A huge variety

During the writing of the present pages I have received from Arizona a letter accompanied with a sketch of a most astonishing mushroom, which my correspondent finds plentifully prevalent in his vicinity, growing in arid sand, even in an exceptionally dry season. He claims that "it is deliciously edible," and he has partaken of it several times. His sketch and description call to mind no existing form of mushroom known to me, though from one peculiarity in particular—namely, its frequently enormous size, "occasionally ten inches in diameter"—one would naturally expect to find it at least notorious, if not famous.

It is plainly an Agaric related to the Campestris, and from the fact of its having "pink gills darker in older specimens" I suspect it to be simply another local masquerade of this same Campestris, which suspicion, by the receipt of further data, I hope soon to verify.