Re: Shitake Mushroom Cultivation

On Sat, 21 May 94 12:42:12 GMT, Del Potter wrote:
>I am a landowner with about 130 acres of mixed forest. I'm interested in
>using the available tan oak trees to cultivate Shitake mushrooms. Does
>anyone have information on any and all aspects of cultivaiton and marketing.

You may already be aware of this but for what it's worth...

Forest Resource Center
1991 Brighsdale Rd.
Route 2, Box 156A
Lanesboro, MN 55949
Phone: (507) 467-2437

Please tell them Steve from ECO-Info sent you.
Steven Hunter
Voice: (612) 783-8391
ECO-Info BBS: (612) 780-7199

ECO-Info, Environmental Information Services (sm)
9145 S. Highway Dr.
Suite #137
Circle Pines, MN  55014


Getting a Year-round Harvest from Japanese Forest Mushrooms

by Albert Bates, Mushroompeople

The shiitake (pronounced she-eh-ta-kay) mushroom is one of the most popular 
foods in Japan and a major staple in China and other parts of the Pacific Rim. 
As a protein source, it has the combined attributes of being appetizing, 
nourishing, dietetic, and healthful. In Japan, it is often eaten three times 
per day.

% Shiitake contains all 8 essential amino acids in better proportion than 

% Shiitake contains a good blend of vitamins and minerals, including vitamins 
A, C, and D, and Niacin

% As little as five grams of shiitake taken daily reduces serum cholesterol 
and blood pressure dramatically

% Shiitake produces interferon and interleukin compounds which strengthen the 
immune response to protect against cancer and virus infections

% Shiitake produces a fat-absorbing compound which aids in weight reduction

Although shiitake has been cultivated in Asia since at least the time of 
Christ, it is still relatively insignificant as a food crop in the West. One 
reason is the confusion of Dept. of Agriculture scientists who mistook 
shiitake's Latin name, Lentinus edodes (oak fungus), for the fungus that 
attacks railroad ties, Lentinus lepideus. USDA instituted a complete quarantine 
on shiitake imports that only ended when the mistake was officially recognized 
in 1972. Today, health conscious cooks are taking a cue from the handful of 
food gourmets who make shiitake a regular part of their diet. 

Shiitake grows on hardwood logs under forest shade where cold running water is 
nearby. In Japan, the shiitake industry is responsible for the retention of at 
least 10 percent of the forest in that country. Without the money which the 
mushroom trade brings in, small farmers would have cut their forests or sold 
the land to developers long ago. With shiitake, they have kept their farms in 
productive forest and used mushroom revenues to support other traditional 
farming activity.

Deep Forestry

"Forestry" as the term is used most often today, literally fails to see the 
forest for the trees. Recently, a soil scientist in Oregon (David Perry at the 
Oregon State University, whose work is reported by Dan Wheeler in the Spring 
1994 of Mushroom The Journal.) microscopically examined about a half a cubic 
foot of untrammelled ancient forest soil and discovered some 7,000 new species 
of life, including arthropods, mites, copepods, centipedes, millipedes, 
wireworms, psuedoscorpions and other organisms. He hopes to have them all 
described by the year 2005. This richness in healthy soils is entirely thanks 
to the workhorses of waste management--the forest fungi. Fungi make up 52 to 55 
percent of forest biomass and about 95 percent of all plant life survives by 
virtue of symbiotic relationships with mycorrhizal fungi. 

Forest management from a myco-optic perspective becomes a task of healthy soil 
replenishment by making available lots of woody wastes together with suitable 
micro-climates for the proliferation of the primary decomposers: bacteria and 
fungi. It involves continuous thinning, pruning and selective harvest--but it 
is aimed at maintaining a full canopy of rapidly-growing, healthy trees above 
and a depth of waste matter in various stages of decay below. In a young forest 
stand, this may require thinning up to 80 percent. In an older stand, perhaps 
only one or two trees can be removed in an acre of forest each decade.

Mushroompeople is a cottage industry of The Farm, an experimental village 
begun in 1971 by Stephen Gaskin and 320 hippies fleeing the Haight Ashbury. Our 
interest in mushrooms dates to that early period of our development, but in 
recent years we have grown increasing concerned about the future of Earth's 
forests and have discovered that mushrooms have something to contribute to 
forest preservation as well. The Farm manages more than 2 square miles of 
hardwood forest as part of our freehold, and we are interested in preserving 
its biological integrity.

One thing we have learned is that the nutritional value of shiitake as a 
protein source and its medicinal and dietetic benefits have made this mushroom 
very popular in Japan and China, encouraging small farmers to keep large areas 
of land forested. We fully expect that health-conscious consumers in North 
America and Europe will develop an interest in shiitake for much the same 
reason. Shiitake cultivation can then serve to protect North American stands of 
hardwoods in much the way it has saved trees in China and Japan.

Since shiitake is one of the easiest mushrooms to grow and the techniques 
developed for shiitake growing carry over to many other saprophytic species of 
mushrooms, learning to cultivate shiitake can lead to a good understanding of 
mushrooms in general. Many people are afraid to begin growing forest mushrooms 
because of early childhood associations of mushrooms as poison. When you 
cultivate particular mushrooms however, you know what to expect and are not 
likely to confuse what comes up with something else that is not good for you. 
Shiitake, with its cracked, fleshy top--deep brown in the center and lightly 
misted with white flecks at the edges--is difficult to confuse with other 
oak-dwelling mushrooms.

Getting Started

Shiitake prospers in sixty percent or better shade outdoors (not darkness) 
where ventilation is good. Running water is needed several times a year but not 
continuously (the bark should dry out between waterings to avoid destructive 
surface molds). Shiitake yards are usually in places one can easily visit 
daily, not too remote from other activities. Indoor production, often used for 
commercial operations where continuous fruiting is desirable, requires 
environments which approximate outdoor conditions, with variable temperature, 
lighting, humidity and ventilation. Many farmers have found converted poultry 
houses and tractor sheds make ideal growing barns.


Oak logs are usually used, but many other hardwoods can also produce shiitake. 
Young, living, healthy trees are selected from stands needing to be thinned. 
Care is taken to avoid damaged bark, sections with bark less than 1/8" thick 
(too fragile!), logs over 7" thick (too heavy!), deadfalls, and logs of 
uncertain age or origin. Among commercial growers, a standard width is 4", cut 
30" to 48" long. Pines and other conifers will not produce shiitake.

The "perfect" time to fell trees is the fall and winter; felling in summer 
produces lots more contamination as well as lowered yield. Winter-felled trees 
may be kept until spring if the internal moisture content remains above 35%, 
but it is recommended to inoculate within 3 weeks of felling, if possible.

Optimal moisture content for spawning is 35 to 45 percent. This is not bark 
moisture, which can be affected by spraying or rainfall, but core moisture, 
which can only be affected by soaking or moisture conservation after cutting.

Strain Selection

There are three basic strain categories: 1) year round fruiting (wide-range); 
2) winter to spring (warm); 3) fall, winter, and spring (cold).

The best types for most uses are the year-round, wide-range strains. These 
produce quickly and easily, so logs turn over more rapidly and less growing 
area is required. Warm weather types are usually grown for dried mushroom 
production, and often require two to three summers after inoculation until the 
first flush. The cold weather types generally fruit two summers after 
inoculation although there are some varieties which will produce mushrooms the 
first fall after spring inoculation. Cold weather strains are most likely to 
produce the highest grade, or what the Japanese call "donko" (flower-petal) 

All strains need one full summer before they will produce. Generally, the more 
spawn you put into a log, the sooner it will produce its first crop when 
environmental conditions are right.


Commercial sources supply spawn in three forms: on wooden plugs (dowels), in 
sawdust, and in grain. Plugs are inoculated by pre-drilling the logs. Sawdust 
is inoculated by either predrilling and using a special pressure inoculation 
tool, or by making a saw-cut and packing the cut with spawn. Grain spawn is 
used to produce mushrooms in a greenhouse, on sawdust or wood chips. The 
standard methods of inoculation are quite simple, so that two workers can put 
up 300 logs in a day.

Wooden-plug spawn (easiest method)

1.      Drill. Use a 5/16" (8.5 mm) drill bit. Beginning two or three inches 
from the end of the log, drill close-spaced rows (2-4" between holes), 11/4" 
deep. Move down the log, drilling rows every 6 to 8 inches until you get 2 or 3 
inches from the other end. 

2.      Hammer. Tap wooden plugs flush with a hammer, leaving air space below.

3.      Wax. Apply hot melted wax to seal in moisture and protect spawn.

Sawdust spawn (commercial technique)

1.      Drill. Use a 3/8" to 5/8" drill bit (7/16 is best), to drill rows of 
holes on 2 to 4-inch centers, 3/4" deep, 6" apart.

2.      Fill. Pack spawn firmly to rim of hole. No air space is necessary.

3.      Wax. Seal with hot wax.

Spawn Run

After inoculating, it takes 4 to 10 months before the log is completely 
colonized by the fungus. Freshly inoculated logs are temporarily stacked in 
square criss-cross tight piles (crib stack) in the shade and covered with 
canvas or polyvinyl for about 2 months. Some growers cover them with shade 
cloth or burlap and after each rainfall uncover the logs to allow the bark to 
dry, to prevent growth of unwelcome fungi. 

Cold temperatures cannot hurt the spawn, although growth will diminish when 
temperatures are below 43!F. Snow cover does not hurt the logs. Spawn can die 
above 100!F, so in the Southern tier, growers protect their logs from 
overheating by watering them and keeping them well-shaded and ventilated.

After 2 months, the logs are restacked in a loose crib stack or a lean-to 
stack. The slant angle is determined by the sunlight, with the objective being 
to keep as little of the log exposed to direct sun as possible (unless air 
temperature is always below 43!F and some solar warming is desirable).  The 
spawn run is nearly complete when fuzzy white blotches appear at log ends or 
mushrooms sprout after a rainfall.  To reduce the chances of contamination by 
wild fungi, some growers rotate spawn yards each year, moving logs to the 
"permanent" laying yard after shiitake mushrooms have appeared.


Once the spawn run is complete, mushrooms can be forced to appear by soaking. 
To get optimum, more or less continuous, production, commercial producers 
"cycle" about 1/7 of their producing logs each week as follows:

1. Logs are soaked for 6-36 hours, depending on temperatures, usually in a 
55-gallon drum, tub or stock tank. If air is warm and water is cool, the soak 
can be 6-12 hrs. If air is cool and water is cool, longer soaking is 
recommended. If bubbles no longer appear on the surface of the logs, they are 
totally saturated and are removed. 

2. Many growers "thump" them into position for fruiting. Some Asian growers 
use mechanical vibrators or electric shock. Many recommend "cold shock" (very 
cold water) as the most effective way to force fruiting.

3. "Pinning" occurs as the primordia push through the bark. Careful management 
during pinning can result in higher yields. Optimal conditions call for 
maintaining the logs between 55 and 65% moisture at 55 to 65!F until small 
bumps form under the bark.

4. There is at least a 30 day wait after a harvest before soaking again. This 
"rest period" is essential to allow the mycelia to store more nutrients.

Some growers use clear poly covers reaching to the ground to control moisture 
loss for several days after soaking. Some use poly to keep rain off the logs 
during the rest period, or during the harvest period (wet shiitake doesn't keep 
as well). Special felt blankets are often used on the West Coast and Northern 
Plains, where excessive drying is a problem. 


The mushrooms are  harvested after the veil breaks while the caps still have 
curled edges and are less than 4 inches in diameter. During cool weather, the 
mushrooms are left on the logs for many days. When it's warm, growers harvest 
early and often, to minimize bug damage and discoloration from spore discharge. 

Fresh shiitake will keep for 2-3 weeks in the refrigerator, but should be 
marketed within 4 to 5 days from picking. They usually reach market in small 
(strawberry) baskets, cloth or paper bags, or in perforated cardboard boxes 
(unsealed). Shiitake which can't be sold fresh locally can be dried and shipped 
to commercial packagers. One packager, Hardscrabble Enterprises of Cherry 
Grove, West Virginia, offers a standard price of $15 per pound, dry weight. 

It is possible to fruit shiitake at any time of year. Therefore the production 
can be scheduled to coincide with labor availability and to keep a constant 
supply in the market. Continuous production encourages consistently high 
prices, typically $3 to $9 per pound, fresh weight. Fresh weight is about 7 
times more than dry weight, so growers usually try to sell shiitake fresh 
whenever there is a local market. 

Left to nature, a log will fruit for as many years as its diameter in inches. 
Forced fruiting speeds crop production but also shortens the productive life, 
since each log has a fixed available quantity of nutrients, which, once 
exhausted, are gone. 

Calculating Production Rates

A one person farm (less than 5000 logs) can produce 45-65 pounds per day (at 
0.25 to 0.33 lb/flush/log). A two person farm (5,000-10,000 logs) can produce 
about 110 pounds per day. A four person farm (20,000-30,000 logs) can produce 
about 220 pounds per day. Labor is needed for soaking the logs, harvesting the 
mushrooms, packaging them, and then selling them. A small farm with perhaps a 
father and his son and hired help in season, inoculating 4,000 logs/yr will 
generate $20,000 to $30,000 pre-tax annual income or about $10 per hour of 
labor, assuming an average sale price of $4 per pound. If a steady buyer at $8 
per pound can be found, returns go up dramatically. For this reason, many 
shiitake farmers devote as much time to marketing as to production, driving 
long distances to service gourmet restaurants and halth food stores.

Shiitake has adequate nutritional qualities to serve as a main dish. It's 
oriental mystique gives it an easy entr
 into the vegetarian/health 
food/gourmet circles. As the baby boomers begin to age (the leading edge is now 
45 and the back edge is 25), they will demand foods that are filling without 
being fattening. Endowed with blood-pressure lowering qualities and a 
demonstrated anti-viral property, shiitake sales could take off quickly as this 
flavorful mushroom becomes for America what it has already become in Japan: a 
popular all-around food.

Returns for Raising Shiitake Mushrooms on One Cord of Wood

All figures are approximate. No cost is assigned to logs or to labor. Logs per 
cord: 300 (4" diameter, 42" long). Inoculation holes per log: 25. Mushroom 
drying ratio: 7 pounds fresh produces 1 pound dry.

Inoculation Costs       Per Cord        Per Log

Using plug spawn: 

1000 dowels/bag, 10 bags @ $35          $350    $1.16

(easier & faster, fewer contaminated logs)

Using sawdust spawn 

15 bags spawn @ $19     $285    $.95

Less expensive, produces mushrooms sooner)

Expected returns over four years - at wholesale prices

All sold fresh: 2.25 pounds/log 

x 300 logs x $4/pound   $2700   $9.00

All sold dried: .325 lbs/log 

x 300 logs x $13/pound   $1267  $4.22

70% sold fresh, 30% sold dried:         $2270   $7.57

>From 1988 to 1991, some 230 U.S. shiitake growers increased production from 
3.7 to 4.1 million pounds and earned from $22 to 22.4 million/year in gross 
sales, about $4.17 per pound. Local wholesale rates vary from $3 to $9 per 

For more information about growing shiitake, we recommend Growing Shiitake 
Commercially by Bob Harris ($13.50), which is available post-paid from 
Mushroompeople (P.O. Box 220 Summertown TN 38483-0220). Mushroompeople, which 
is the oldest shiitake spawn company in North America, also offers a free 
catalog with a wide selection of shiitake spawn, tools and equipment. A starter 
kit for beginners, with everything you need to inoculate ten logs for your home 
kitchen, sells for $19. 

PO Box 220 / 560 Farm Rd.
Summertown TN 38483-0220
Email: NATLAW@igc.apc.org
Int'l Voice/Fax: (int. code +) 615-964-2200
U.S. Fax: 1-800-MYCOFAX

Copyright 1994 The Second Foundation

Sender: "brianmc" <brianmc@aol.com>
Subject: MycoInfo  (Jan, 12, 1994)

****MYCOINFO  JAN 12, 1994****
The following is something I considered so important, that rather than
excerpt portions of it, I'm reposting it in it's entirety.  The original was
a post from Marc Alter to T J Crebs

Date:   94-01-12 19:42:28 EST
From:  TJCrebs
Subj:   Re: Florida Cultivation Message
To:      Allanmar, BrianMc

Brian & Allan,

A Post from Marc Alter which I thought you both would like: Allan for growing
more PA-shiitake and Pa-Oysters and Brian maybe for adding to his MycoInfo.
Marco is very good. Make sure you give him your regards.             Regards,

P.S. I put on the Mushroom Folder--the 2nd-most active folder on the
Gardening Exchange with 50 postings, yeah!!!

Forwarded Message:

Date:   94-01-11 17:53:49 EST
From:  Malter
Subj:   Re: Florida Cultivation Message
To:      TJCrebs


Here is the article.  I started to chop it up for posting at one time but ran
out of patience/interest/time.  Feel free to perform surgery on it!


From:  Stephen L. Peele [72253,1553]


You have my permission to run the said mushroom articles on
America OnLine.  You might also mention that FMRC is making plans to open a
Mushroom Conference Forum on INTERNET.  This should come about within the
next two months.  Persons who are interested in linking up should contact me
thru E-Mail for more information.  Stephen L. Peele/FMRC

Taken from "THE MUSHROOM CULTURE", The Journal Of Mushroom Cultivation,
Issue Number #21, July 1993.....Published by FMRC


By STEPHEN L. PEELE, Curator, Florida Mycology Research Center (FMRC),
P.O. Box 8104, Pensacola, FL  32505
(CIS i.d. = 72253,1553)

Taken from "THE MUSHROOM CULTURE", The Journal Of Mushroom Cultivation,
Issue Number #4, Jan. 1985

Cultivating Techniques for the Shiitake Mushroom, Lentinus edodes

     The Shiitake Mushroom is indeed taking America.  There are many
reasons pushing this boom.  Not only do they taste great, many now believe
this mushroom holds powerful medicinal compounds that not only prevent
cancers, but also induce the production of interferon, and reduce the
serum chloresterol levels.  Because these mushrooms are grown on wood,
they lack that "earthy" taste which many dislike about the button mushroom
(the ones seen most offten in the grocery store).  This gives the Shiitake
even more followers, who before, did not like mushrooms.  One of the
following cultivating methods describes the use of oatmeal.  Mushrooms
grown on oatmeal are by far the very best.  These mushrooms may even
develop a special market.

Log Method

     This has been the traditional method of the Japanese for thousands of
years.  It has also been the choice of commercial production in this
country.  Hardwood logs are used, oak (except the evergreen oaks), alder,
maple, and chestnut.  The logs are cut from live trees, and in the winter
while the sap is down.  A five inch diameter, and 2 1/2 foot length log
is a good standard.  All branches should be removed, and careful
attention should be given not to damage the bark in any way.

     After being cut, the logs are then dried out, away from direct sun
light, and up off the ground.  This can take from 30 to 90 days.  Drill
six to eight holes about the log using all sides.  If wooden dowel spawn
is used, the holes are placed 3/4 of an inch deep, and are wide enough so
that the dowel fits snug.  If sawdust spawn is used, the holes should be
1/2 inch wide.  Warm wax, or plastic plugs are used to seal points of
inoculations.  Some growers claim that inoculation of the logs as soon as
they are cut, because of the higher moisture content, is best.  Others
state that the drying destroys the natural resistance defenses of the
log, allowing the spawn to run best.  The logs are stacked up like
firewood, up off the ground, and in a shaded area.  Logs outside will
stay dormant until spring.  To start immediate growth, the logs are held
at 72 degress F.  After four to six months of growing, the mycelium will
break out from the ends of the logs.  When this occurs, the logs will be
ready to fruit.

     Whether you inoculate in dry or fresh logs, the 72 degree F
temperature factor will mainly determine the length of time for the growth
period.  A 50-60 percent moisture content should be maintained on the
logs.  Logs left out side may not produce fruit until the second year. 
Logs held in a controlled environment at 72F should fruit the following

     To induce pinning, the logs are soaked in water.  They also can be
sprayed with water for 14 hours.  Within seven days primordia development,
the birth of small mushrooms, should be observed.  Within several days the
mushrooms will mature (3-6).  From the second year on, mushrooms can be
produced in the spring also.  One log can produc better than one pound
each year, and they can produce fruit for up to five years.

Other Methods

     Sawdust from the proper logs can be mixed 4:1 with bran.  As with the
logs, a 50-60 percent moisture content is best.  The sawdust/bran mixture
is sterilized.  After inoculation, it is held at 72F.  Sawdust alone can
be used, but bran is needed as a casing, causing an extra step, and
longer growth period.  No light is needed.  To induce pinning, the
sawdust blocks are soaked in water like the logs.  62F temperature and
the addition of filtered natural light enhance this stage.

     Hickory Chips can now be used for production of these mushrooms with
a new strain of Shiitake developed by FMRC.  This new strain, simply
called "Hickory Chip Strain", now makes the home cultivation of this
mushroom easier than ever.  Because bread molds, yeasts, and other
contaminants can not grow on these chips, they indeed make the ultimate
substrate (Hickory chips can be found next to the charcoal in most
supermarkets).  The use of thse chips eliminates the number one reason
for mushroom crop failure, contamination.  Hickory chips with mycelia
growth are simply added to chips which have been moistened.  A casing of
bran is sometimes needed for pinning, but if chips have good bark
content, fruiting occurs without casing.  Several good sized chips, well
taken with "hickory Chip Strain", are available from FMRC.  No sterile
technique is required.

     Spawn runs using the above methods is much faster than using logs. 
Within 30-65 days after inoculation blocks are fully taken by the
mycelium.  Hence, these methods produce mushrooms much quicker, within
four months.

Oatmeal Method

     This method uses oatmeal as the fruiting substrate.  Using oatmeal
is more difficult.  Because it will support a lot of other growths,
contamination must be controlled.  Home growers should use quart canning
jars for sterile chambers.  Add 2/3 cup of oatmeal, and 1 1/3 cups
distilled water into the jar.  Place sealing edges up so that jars will
not seal (this rubber seal must be up and not against the jar).  Leave
the screw band loose so that jar will not seal.  You do not want the jar
to seal.....if it does, it will explode inside the pressure cooker when
it is sterilized.  Set pressure at 15-20 lbs and cook for 40-45 minutes.
The jars are then taken out and placed in a sterile area where they are
left to cool.  The cooling area must be sterile or the air that will be
pulled back into the jar as it cools will be loaded with contaminants. 
This will cause for sure failure.  After the jars have cooled, they are
inoculated, and held at 72F.  Filtered natural light is given daily. 
This method can produce fruit within 19 days.  If pinning does not occur
soon after oatmeal has been taken, simply place the chambers in the
refrigerator.  Within several days, primordia should be observed.  The
jars are then uncovered and sat out to fruit.  The room or compartment
used for this fruiting stage should have a high humidity.....85-100
percent.  Jars will produce several good flushes until the oatmeal can no
longer support growth.  

     There are some other methods of inducing pinning if this problem
occurs.  The bark plays an important role of stimulating the mycelium into
fruiting.  When aqueous extracts of oak bark were tested, it stimulated
the fruiting of this mushroom.  It has been found that nickel and tin are
the stimulatory factors.  Either of these two inorganic elements will
stimulate fruiting when added in small concentrations (ppm).  Many thanks
to Gary F. Leatham, Ph.D., USDA Forest Service, and to Bob Harris of
MUSHROOMPEOPLE for their help in this research.

Cultivating Techniques for the Pleurotus ostreatus, the Oyster Mushroom

By STEPHEN L. PEELE, Curator, Florida Mycology Research Center (FMRC),
P.O. Box 8104, Pensacola, FL   32505
(CIS i.d. = 72253,1553)

Taken from "THE MUSHROOM CULTURE", The Journal Of Mushroom Cultivation
(TMC), Issue number #1, April 1984

     This mushroom has a light colored cap that is shaped like an oyster
shell.  When found in the wild, they sometimes appear in large overlapping
(imbricate) clusters.  It is found on dead wood.  The oyster-shell-like
caps, no stalk, sessile growth habit, and gills extending down to the
base, are the distinctive characteristics of this mushroom.  It has a
white to buff spore print.  The Pleurotus sapidus is a variant of the
Pleurotus ostreatus.  It is also referred to as Pleurotus floridia because
it is mainly only in Florida.  It has a lilac-colored spore print.  Both
of these mushrooms are choice edibles.  It has a fragrant ordor, sometimes
that of anise.....especially the Pleurotus sapidus.

AGAR - Malt Extract Agar:  Malt Extract 20 Grams.  Agar 15 Grams.  Peptone
5 Grams.  Water 1 Liter.

SPAWN JARS - Barley, and rye grain do very well.  It is important to use
the spawn before it "sets".  After taking over the jar, the mycelium will
start to set, or turn hard.  Once this happens, the spawn will not
inoculate the fruiting substrate properly.  Once the grain is fully
taken.....use the spawn then.  Keep the spawn jars 80 degrees F for best

FRUITING - Several substrates can be used to cause fruiting.  Straw, a 4
to 1 mixture of sawdust and bran, and even news paper has been used. 
Logs from many different trees can be used including willow, aspen,
beech, and even pine.  See how to prepare logs in #4 TMC, Shiitake
Cultivation.  Sterilized wheat straw gives great results.  Here is a real
easy method.  Take a large Reynold's oven cooking bag and place the straw
inside.  Use wet straw with 80 percent moisture content.  After
sterilizing, you will then have a sterile chamber with media.  Once
cooled, it is then inoculated with spawn from the grain jars.  PVC
fittings can be used to incorporate filter.  A .3 micron is best.  Or,
bag is placed in sterile area and a few small holes are put in the bag
with a knife.  This is to allow CO2 exchange.  Hold temperature at 80
degrees F.  Light is not needed for this stage.  Keep high humidity. 
Once the straw is fully taken over, you are then ready for the next step.
With this type of mushroom, no casing is needed.  A drop in temperature
along with filtered sunlight is all that is needed to cause pinhead
initiation.  Fluorescent lighting will also do fine.  Drop temperature to
55 degrees F. and set light for 12 - 14 hours a day.  Sometimes just
placing the project in the home refrigerator will start pinhead
initiation.  This will happen in about two weeks.  Once the young
mushrooms have started, the project is then placed in a warmer location
of 65 degrees F.  The bag may also be removed at this stage.  Use the
same amount of light, or just simply place out in the open where filtered
sunlight can be used.  Keep moist, don't let the project get dry.  Spray
with water every day if it is needed (never use city tap water with any
mushroom cultivation.  It contains chlorine).  Mushroom production will
usually equal the weight of the straw when it was dry.

     Several strains of pleurotus ostreatus produce laccase. 
Pleurotolysis is also produced by a specific strain.  The antiviral
antibiotic "Pleuromutilin" is extracted from the Pleurotus passeckerianus.