Mushroom spawn.
What is mushroom spawn? Is it
a seed or a root? Do you plant it or sow it,
or how do you prepare it? are some of the questions
asked me now and again. To the general public
there seems to be some great mystery surrounding this
spawn question; in fact, it appears to be the chief
enigma connected with mushroom-growing. Now, the
truth is, there is no mystery at all about the matter.
What practical mushroom growers call spawn, botanists
term mycelium.
The spawn is the true mushroom plant
and permeates the ground, manure, or other material
in which it may be growing; and what we know as mushrooms
is the fruit of the mushroom plant. The spawn
is represented by a delicate white mold-like network
of whitish threads which traverse the soil or manure.
Under favorable circumstances it grows and spreads
rapidly, and in due time produces fruit, or mushrooms
as we call them. The mushrooms bear myriads of
spores which are analogous to seeds, and these spores
become diffused in the atmosphere and fall upon the
ground. It is reasonable to suppose that they
are the origin of the spawn which produces the natural
mushrooms in the fields, also the spawn we find in
manure heaps. But we never have been able to produce
spawn artificially from spores, or in other words,
mushrooms have never been grown by man, so far as
I can find any authentic record, from “seed.”
How, then, do we get the spawn? By propagation
by division. We take the mushroom plant or spawn,
as we call it, and break it up into pieces, and plant
these pieces separately in a prepared bed of manure
or other material, under conditions favorable for
their growth, and we find that these pieces of spawn
develop into vigorous plants that bear fruit (mushrooms)
in about two months from planting time. When
the spawn has borne its full crop of fruit it dies.
Well, then, if we can not produce
spawn from spores, and the spawn in the beds that
have borne mushrooms has died out, how are we to get
the spawn for our future crops? is a question that
may suggest itself to the inexperienced. By securing
it when it is in its most vigorous condition, which
is before it begins to show signs of forming mushrooms,
and drying it, and keeping it dry till required for
use. But in order to secure the spawn we need
to take and keep with it the manure to which it adheres
or in which it is spreading. In this way it can
be kept in good condition for several years and without
its vitality being perceptibly impaired. Keeping
it dry merely suspends its growth; as soon as it is
again submitted to favorable conditions of moisture
and heat its pristine activity returns.
Mushroom spawn can be obtained at
any seed store. Our seedsmen always keep it in
stock, both the brick (English), and the flake (French)
spawn. It is retailed in quantities of one pound
or more, and as the article is perfectly dry it can
be easily sent by mail in small quantities.
The seedsmen import it from Europe
every year along with their seeds. A prominent
Boston seedsman writes me: “We get our supply
through the London wholesale seedsmen, for the sake
of convenience and cheaper ocean freight, etc.
Coming with a shipment of other goods and on same bill
of lading brings the freight charges down. The
low price at which mushroom spawn is sold in quantity
can only be maintained with low freight rates, as
there is a duty here of 20% on the article.”
By direct inquiry of the leading importers
in different cities I find that we import about 4500
lbs of French or flake spawn, and 4000 bushels, or
64,000 lbs of English or brick spawn, and that fully
a half of this whole importation is handled by the
seedsmen of New York city. In New York one firm
alone, who make a specialty of supplying market gardeners,
has in one year imported 1500 bushels of brick spawn.
But the vicinity of New York is the great mushroom-growing
center of the country, also the best market for mushrooms
in the country. One gardener at Jamaica, L. I.,
bought 1000 lbs of brick spawn at one time, and a
neighbor of his bought 400 lbs; this shows what a large
quantity of spawn market gardeners require. And
the demand this year is unprecedented; some of our
leading importers had sold out their supply before
the first of November. And it is not private growers
so much as market growers who are the cause of this;
the market men find there is money in growing mushrooms
and they are going into it.
Spawn comes in the form of dry, hard,
solid manure bricks, and also in the form of flakes
of half rotted strawy manure. These bricks and
flakes are completely permeated with the mushroom
mycelium.
The brick spawn is commonly known
as English spawn, and what is imported into this country
is made in England, mostly about London. The bricks
made by the different manufacturers vary a little in
size and weight; in some cases ten bricks go to the
bushel, in others fourteen, and in others sixteen.
This last is the commonest sized brick, and weighs
exactly a pound, and measures about eight and one-half
inches long, five and one-fourth inches wide, and
one and one-fourth inches thick; it is what the London
spawn makers call a 9x6x2 inch brick, but it shrinks
in drying. In retailing brick spawn in this country
it is sold by weight and not by measure.
Mill-track mushroom spawn is advertised
by some of our seedsmen, but what they sell under
this name is only the ordinary English brick spawn.
One of our prominent seed firms who advertise it write
me: “Genuine mill-track spawn used to be
the best in England, but it has been superseded, although
European gardeners still call for English spawn under
the name of ‘mill-track.’” The real
mill-track spawn is the natural spawn that has spread
through the thoroughly amalgamated horse droppings
in mill-tracks or the cleanings from mill-tracks.
It is usually sold in large, irregular, somewhat soft
lumps, and is much esteemed by spawn makers for impregnating
their bricks, but nowadays, that horses have given
place to steam as a motive power in mills, we have
no further supply of mill-track spawn for use in spawning
our mushroom beds. We do not feel this loss,
however, as the spawn now manufactured by our best
makers will produce as good a crop of mushrooms as
the old mill-track natural spawn used to do.
The flake spawn is what is generally
known as French spawn, and is imported into this country
from France. But the manufacture of “French”
spawn for sale, however, is not strictly confined to
France. It is put up in two ways, namely, nicely
packed in thin wooden boxes, each containing two or
three pounds of spawn, and also loose in bulk when
it is sold by weight or measure.
Virgin spawn is what we call natural
spawn or wild spawn; that is, the spawn that occurs
naturally in the fields, in manure piles, or elsewhere,
and without any artificial aid. It is supposed
to be produced directly from the mushroom spores,
and is not a new growth of surviving parts of old
spawn that may have lived over in the ground.
It is far more vigorous than “made” spawn,
and spawn makers always endeavor to get it to use
in spawning the artificial spawn. It is seldom
used for spawning mushroom beds because not easy to
obtain. Now and again we come upon a lot of it
in a manure pile; it looks like a netted mass of white
strings traversing the manure. As soon as discovered
secure all you can find, bring it indoors to a loft,
shed, or room, and spread it out to dry; after drying
it thoroughly keep it dry and preserve and use it as
you would French spawn, for it is the best kind of
flake spawn. In using virgin spawn for spawning
beds I have obtained larger and heavier mushrooms
than from “made” spawn, and the beds lasted
longer in good bearing, but the weight of the whole
crop has not been more than from artificial spawn.
How to Keep Spawn.- Spawn
should be kept in a dry, airy place, somewhat dark,
if convenient, and in a temperature between 35 deg.
and 65 deg.. Wherever things will “must,”
as in a cellar, cupboard against a wall, or in a close,
damp building, is a very poor place for keeping spawn.
If the spawn is perfectly dry and kept in a dry, airy
place, and not in large bulk, and covered, it will
bear a high temperature with apparent impunity, but
whenever dampness, even of the atmosphere, is coupled
with heat, the mycelium begins to grow, and this,
in the storeroom, is ruinous to the spawn. Judging
from our natural mushroom crops, the spawn for which
must be alive in the ground in winter, one concludes
that frost should not be injurious to the artificial
spawn, still my experience is that hard frost destroys
the vitality of both brick and flake spawn. And
this is one reason why I get our full supply of spawn
in the fall and keep it myself rather than submit it
to the mercy of the seed store.
New Versus Old Spawn.- How
long spawn may be kept without its vitality becoming
impaired is an unsettled question, but there is no
doubt, if properly kept, it will remain good for several
years. But I can not impress too strongly upon
the reader the importance of using fresh spawn.
Do not use any old spawn at any price; do not accept
it gratis and ruin your prospect of success by using
it. It takes three months from the time when
the manure is gathered for the beds until the mushrooms
are harvested. Can you, therefore, afford to spend
this time, and undergo the care and trouble and expense,
and court a failure by using old spawn? We have
risks enough with new spawn, let alone old spawn.
I do not use any more old spawn, but I have used it
often and long enough to be convinced of its general
worthlessness, unless preserved with the greatest
care.
How to Distinguish Good from Poor
Spawn.- This is a very difficult matter,
notwithstanding what people may say to the contrary.
If we could positively tell good from bad spawn, we
would never use bad spawn, and, therefore, with ordinary
care, have very few failures in mushroom-growing;
for good spawn is the root of success in this business.
Spawn differs very much in its appearance; sometimes
the bricks show very little appearance of the presence
of spawn, and still are perfectly good; and again,
we may get bricks that are pretty well interlaced
and clouded with bluish white mold or fine threads,
and this, too, is good. When the bricks are freely
pervaded with pronounced white threads this is no
sign that the spawn is bad. Bricks dried as hard
as a board may be perfectly good; so, too, may be
those that are comparatively soft. Mushroom spawn
should have a decided smell of mushrooms, and whatever
cobweb-like mold may be apparent should be of a fresh
bluish white color, and the fine threads clear white.
Prominent yellowish threads or veins are a sign that
the mycelium had started to grow and been killed.
Distinct white mold patches on the surface of the
bricks indicate the presence of some other fungous
parasite on the mushroom mycelium; the absence of
any mushroom smell in the spawn indicates its worthlessness
and that the mycelium is dead. One familiar with
mushroom spawn can tell with considerable certainty
“very living” spawn and “very dead”
spawn, but I am far from convinced that any one can
decide unhesitatingly in the case of middling or weak
spawn.
Mr. S. Henshaw, in Henderson’s
Handbook of Plants, tells us: “The quality
of the spawn may be very easily detected by the mushroom-like
smell, ... and I should have no hesitation in picking
out good spawn in the dark.” Sanguine,
surely, but I have tried it and found the test wanting.
M. Lachaume says that good spawn shows “an abundance
of bluish-white filaments well fitted together, and
giving off a strongly marked odor of mushrooms.
All those portions which show traces of white or yellow
mold or have a floury appearance, should be rejected
and destroyed.” Mr. Wright says: “A
brick may be a mass of moldiness, and yet be quite
worthless; and if the mold has a spotted appearance,
as if fine white sand had been dredged on and through
the mass, it is certain there is no mushroom-growing
power there.... If thick threads pass through
the mass and there are signs of miniature tubercles
on them, then the spawn may be regarded as too far
gone.... Clusters of white specks on the spawn
denote sterility.”
Mr. A. D. Cowan, of New York, who
has the reputation of being an excellent judge of
mushroom spawn, writes me: “To correctly
judge the quality of brick spawn by its appearance
requires experience in handling it, and a trained
eye which enables one quickly to detect good from bad,
fair to middling. As two lots seldom come exactly
or nearly alike in appearance, it is hardly possible
to give precise rules to follow, excepting the never-failing
requisite which the spawn must possess to be good,
namely, the moldy appearance on the surface, the more
the better, without showing threads. Too many
of these to a given space are a sure indication of
exhausted vitality, arising generally from the bricks
being heaped together when in process of manufacture,
before they are sufficiently dried. Healthy bricks
are usually of a dusty brown color, and of light weight.
Black colored spawn is to be avoided, as a rule, and
when the black appearance is very prevalent in a cargo
of bricks it is a strong indication that the spawn
has not run its course; and as it is not expected
to do so after it has reached the hands of the retailer
it is economy to cast it aside. Some persons break
a brick into several pieces to see how it looks inside.
To the experienced eye this is not necessary, or even
to lay hands upon it, as the outward moldy appearance
is the best of all evidence of its healthy vitality,
and this never exists if the bricks have lost their
germinating power, excepting, of course, where they
have been kept damp, and the spawn has spent its power,
which is detected by the white threads appearing in
great quantity.”
American-made Spawn.- So
far as I have been able to find out by diligent inquiry,
mushroom spawn is not made for sale in this country.
But I am informed that a few growers do save and use
their own flake spawn. Some of our principal
growers, Van Siclen, Gardner, and Henshaw, for instance,
in time past attempted to make their own spawn, but
with only partial success, and now they confine themselves
to the imported article. But this state of affairs
can not long continue. The demand here for fresh
mushrooms is so great, the industry of mushroom-growing
so important, the price of imported spawn so high,
and the quantity of foreign spawn imported annually
into this country is so large, that, before long,
we hope some one will find it to his advantage to make
a specialty of growing mushroom spawn in this country
to supply the American market. There is no practical
operation in connection with the cultivation of mushrooms
so little known or understood by the general grower
as the growing (or “making,” as it is commonly
called) and preserving of mushroom spawn. General
cultivators in England and France (outside of the
Paris caves) do not make their own spawn; it is a
distinct branch of the business, and carried on by
specialists who grow mushrooms for sale in winter,
and spawn in summer.
The time and attention required to
produce a small quantity of first-class spawn are
worth more than the cost of the spawn at the seed
store. In order to make spawn profitably we must
make it in large quantity, and we need not attempt
to make it unless we have good materials and conditions
for its proper preparation, and will give it every
attention possible for its best development.
Because spawn may be made in America
is no reason whatever why the American people will
buy it. We must produce, at least, as good an
article as the best in Europe before we can find countenance
in our home market. It is not the shape of the
manure brick, its size, fine finish, hardness, softness,
or freshness, that counts in this case; it is the
fullness and vitality of the mass of mycelium or mushroom
plant that is contained within it.
HOW TO MAKE BRICK SPAWN
As the making of brick spawn for sale
is not yet an American industry, but almost entirely
confined to England, I think it best to restrict myself
to describing how it is made in England. Mr. John
F. Barter, of Lancefield street, London, is one of
the most successful mushroom growers and spawn makers
in Great Britain. He writes me that he confines
himself entirely to the mushroom business; he makes
his living by it. He grows mushrooms in the winter
months and makes spawn in the summer months; he employs
men for mushroom bed making from August until March,
then, to keep on the same hands during summer, he makes
spawn for sale. He grows for and sells in the
London market about 21,000 pounds of mushrooms a year,
and in summer makes some 10,000 bushels, equal to
160,000 pounds, of brick spawn for sale. The amount
of spawn made in a year by this one manufacturer is
about three times as much as the total annual importation
of mushroom spawn of all kinds into this country.
And he is only one maker among several. This
fact alone must convince us that mushroom-growing
is carried on to a vastly greater extent in European
countries than it is here, where we have as good facilities
as they have, and an immensely better market.
The manner of making the spawn differs
a little with the different manufacturers, and no
one can become proficient in it without practical
knowledge. I asked Mr. Barter if he thought spawn
could be made profitably in this country, paying,
as we do, $1.50 a day for laborers, and without any
certainty of the same men staying with us permanently.
He writes me: “Uncertain labor would be
of no use. Of course the wages you pay would
not affect it much, as I pay nearly as much as that
for my leading men. But to begin with, you must
have a man that has had some experience.”
About the simplest and best way of
making brick spawn that I find described is the following
from The Gardeners’ Assistant. I
may here state that Robert Thompson, the author of
this work, was for many years the superintendent of
the Royal Horticultural Society’s gardens at
Chiswick, near London, and, in his day, was regarded
as without a peer in practical horticulture, and lived
in the midst of the market gardens of London and the
principal mushroom-growing district.
“Fresh horse droppings, cow
dung, and a little loam mixed and beaten up with as
much stable drainings as may be necessary to reduce
the whole to the consistence of mortar. It may
then be spread on the floor of an open shed, and when
somewhat firm it may be cut into cakes of six inches
square. These should be placed on edge in a dry,
airy place, and must be frequently turned and protected
from rain. When half dry make a hole in the broadside
of each, large enough to admit of about an inch square
of good old spawn being inserted so deep as to be a
little below the surface; close it with some moist
material the same as used in making the bricks.
When the bricks are nearly dry make, on a dry bottom,
a layer nine inches thick of horse dung prepared as
for a hotbed, and on this pile the bricks rather openly.
Cover with litter so that the steam and heat of the
layer of dung may circulate among the bricks.
The temperature, however, should not rise above 60
deg.; therefore, if it is likely to do so, the
covering must be reduced accordingly. The spawn
will soon begin to run through the bricks, which should
be frequently examined whilst the process of spawning
is going on, and when, on breaking, the spawn appears
throughout pretty abundantly, like a white mold, the
process has gone far enough. If allowed to proceed
the spawn would form threads and small tubercles,
which is a stage too far advanced for the retention
of its vegetative powers. Therefore, when the
spawn is observed to pervade the bricks throughout
like a white mold, and before it assumes the thread-like
form, it should be removed and allowed to dry in order
to arrest the further progress of vegetation till
required for use. It ought to be kept in a dark
and perfectly dry place.” I would add,
do not keep it where it is apt to become musty or
moldy in summer; also keep it in as cool a dry place
as possible in summer, and always above 35 deg.
in winter.
These other recipes are also given:
“1. Horse droppings one
part, cow dung one-fourth, loam one twentieth.
“2. Fresh horse droppings
mixed with short litter one part, cow dung one-third,
and a small portion of loam.
“3. Equal parts of horse
dung, cow dung, and sheep’s dung, with the addition
of some rotten leaves or old hotbed dung.
“4. Horse dung one part,
cow dung two parts, sheep’s dung one part.
“5. Horse droppings from
the roads one part, cow dung two parts, mixed with
a little loam.
“6. Horse dung, cow dung, and loam, in
equal parts.”
From the above it appears that horse
dung and cow dung are the principals in spawn bricks;
the loam is added for the purpose of making the other
materials hold together; it also absorbs the ammonia,
which otherwise would pass off.
J. Burton’s Method.- From
The Kitchen and Market Garden. Make
the spawn in early spring. As cow manure is the
principal ingredient used in making the bricks this
should be secured before the animals get any green
food. Store it on the floor of an open, dry, airy
shed, and turn it every few days for a week or two.
Then add an equal part of the following: Fresh
horse droppings, a little loam, and chopped straw,
mixed together. “The whole should then be
worked well together and then trodden down, after
which it may be allowed to remain for a few days,
when it will be required to be turned two or three
times a week. If the weather be fine and dry
the mass will soon be in a fit condition for molding
into bricks, which process can be performed by using
a mold in the same way as the brick makers, or, ...
the manure may be spread evenly on the floor to a
thickness of six inches, and then be firmly trodden
and beaten down evenly with the back of the spade.
It should then be lined out to the required size of
the bricks, and be cut with a sharp spade or turfing
iron. In a few days the bricks will be sufficiently
dry to handle, when they should be set up edgeways
to dry thoroughly, and if exposed to the sun for two
or three days they will be ready to receive the spawn.
In introducing the spawn two holes large enough to
admit a piece of spawn as big as a pigeon’s egg
should be cut in each brick at equal distances.
This should be well beaten in and the surface made
even with a little manure. The bricks should then
be collected together in a heap and covered with enough
short manure to cause a gentle heat, being careful
that there is no rank heat or steam to kill the spawn.
This must be carefully attended to until the spawn
is found to have penetrated through the whole of the
bricks, after which they should be stacked away in
any convenient dry place.”
How to make French (flake) spawn.
I can not do better than to let a
practical Frenchman engaged in the business tell this
story. In Vol. XIII of the London Garden
I find an English translation of M. Lachaume’s
book, “The Cave Mushroom,” and this comment
by the editor: “The most complete account
of the cave culture of mushrooms which has been published
by any cultivator on the spot well acquainted with
the subject is that recently published by M. Lachaume.”
Lachaume says: “The best
spawn to use is what is called ‘virgin spawn’;
that is to say, which has not yet produced mushrooms.
In this country this kind of spawn may be procured
of any respectable nurseryman, under the name of ‘French
spawn.’ It differs from English spawn by
being in the form of small tufty cakes, instead of
in compact blocks. Large mushroom growers, however,
always provide themselves with their own spawn by
taking it from a bed which is just about to produce
its crop, or which has already produced a few small
mushrooms.... It is true that by thus ‘breeding
in and in,’ as it were, the mushrooms show a
tendency to deteriorate after a time; new spawn must
therefore be obtained as soon as any signs of deterioration
begin to manifest themselves.”
Making French Virgin Spawn.- Condensed
from Lachaume’s book on mushrooms. Take
five or six barrow loads of horse droppings that have
lain in a heap for some time, and lost their heat,
and mix them with one-fourth of their bulk of short
stable litter. Then, in April, open a trench
two feet wide, twenty inches deep, and length to suit,
at the foot of, but eight inches distant from, a wall
facing north. In the bottom of the trench spread
a layer three to four inches deep of chopped straw,
then an equally thick layer of the prepared manure,
all pressed firmly by treading it down. The two
layers must now be gently watered, and then another
double layer of chopped straw and droppings must be
laid, trodden down and watered, and so on until the
top of the trench is reached. The bed ought to
rise above the level of the ground and be rounded
off like the top of a trunk. To prevent excessive
dampness from heavy rain cover the mound with a thick
layer of stable litter. Three months after filling
the trench it should be opened at the side or end.
If the pieces of manure are well covered with masses
of bluish-white filaments, giving off the odor of
mushrooms, the operation has succeeded, and the spawn
is fit for use or for drying to preserve for future
use. But if the threads are only sparingly scattered
through the mass, the trench should be covered up
again and left for another month. In saving the
spawn the flakes of manure containing the largest amount
of spawn filaments should be retained, and those showing
a brown appearance rejected. In order to facilitate
the drying of the spawn the flakes should be broken
into pieces, weighing from one to two pounds; they
are then placed in a well ventilated shed, but they
must not be piled upon each other. Properly prepared
and dried this spawn keeps good for ten years.
A Second Method- (by Lachaume).
“This is generally adopted by mushroom growers.
The formation of the spawn is accelerated by adding
pieces of old spawn here and there.... At the
beginning of April we must choose a piece of ground
situated at the foot of a wall facing north....
The soil ought to be very open and light rather than
heavy, so as to avoid dampness. Taking advantage
of a fine day, we open a trench sixteen inches wide
and at about eight inches from the foot of the wall,
and of a length adapted to the quantity of spawn we
desire to produce. The earth is thrown out on
the side opposite the wall. Manure which has been
prepared for a mushroom bed, and has just come into
condition is then filled into the trench, leaving,
however, a space at one end of it about two feet and
six inches in length for the formation of a mushroom
bed, which is made by tossing the manure about and
shaking it up with the hands, after which it is pressed
down with the hands and knees. As soon as the
layer of manure reaches six inches in thickness we
place along the edge a number of lumps of spawn at
about one foot apart. These lumps are placed
level with the manure on the edge facing the wall.
This portion of the surface of the manure ought to
be raised vertically, and should lean against the
earthen wall of the trench. The other half of
the surface ought to slope gently toward the wall,
leaving a space of three or four inches between it
and the side of the trench, so that it may be trimmed.
The lumps of spawn on this surface should be placed
a little backward, so that they may not be broken
when the bed is trimmed. The bed is then covered
with more manure, until the first lumps of spawn are
buried three or four inches deep. A second row
of lumps of spawn is then inserted, as described in
the directions for making the first row, and the bed
is filled up level with the surface of the soil.
It is finished by covering it up with a layer of fine,
dry soil three or four inches thick. The spawn
ought to be very dry, otherwise we shall get a premature
crop of mushrooms instead of fresh spawn. At the
end of six weeks or a couple of months the new spawn
ought to make its appearance, a fact which we may
learn by opening the bed. One sign, which will
save us the trouble of opening up the beds, is the
appearance of young mushrooms on the surface.
The layer of earth is first removed, and then the
cakes of spawn are treated as described in the directions
given for the first method of making spawn.”
Third Method- (by Lachaume).
“By filling in a trench like that described
in the first method, by a series of layers of one-third
of pigeon or fowl guano, and two-thirds of short manure,
containing a large proportion of spent horse droppings,
treading it down firmly, watering it if it is too
dry, and finishing up with a layer of soil, as described
already, we may, at the end of a couple of months,
or even a little longer, procure a supply of well-formed
cakes of spawn of excellent quality, which may be
used in the ordinary manner.”
From Mr. Robinson’s “Mushroom
Culture.” “This (French) spawn is
obtained by preparing a little bed, as if for mushrooms,
in the ordinary way, and spawning it with morsels
of virgin spawn, if that is obtainable; and then when
the spawn has spread through it, the bed is broken
up and used for spawning beds in the caves, or dried
and preserved for sale.”
From Mr. Wright’s book on mushrooms.
“French spawn ... is contained in flakes of
manure. Neither is it virgin spawn, nor derived
immediately from it, ... but is spawn taken from one
bed for impregnating another.”
Relative Merits of Flake and Brick
Spawn.- The flake or French spawn costs
about three times as much as the brick or English spawn,
and, as it is so much whiter with mycelium than is
the brick spawn, many believe that it is more potent
and well worth the additional cost. In spawning
the beds I use two pounds of flake spawn to plant the
same space for which I would use five pounds of brick
spawn, and this gives a capital crop, with number
of mushrooms a little in favor of the flake spawn,
but on account of the larger size of the mushrooms
the weight of crop is considerably in favor of the
brick spawn. And I find more certainty of a crop
in the case of the brick spawn than in the other.
Regarding the respective merits of
brick and flake spawn, Mr. Barter, in response to
my inquiry, writes me: “I have tried them
both, and know brick spawn to be far the best.
You see, I do nothing but this mushroom business for
a living, so, of course, would use the best kind of
spawn for my crop. Generally the French spawn
produces one-third less mushrooms than does the brick
spawn from the same length of bed, besides, those
from the brick spawn are by far the heaviest and fleshiest.”
I would here observe that Mr. Barter’s
remarks apply more to ridge beds out of doors than
beds in the cellar or mushroom house. And it is
odd, but true, that the flake spawn does not produce
as good results in outdoor beds as it does in those
under cover.