North Spore Organic Italian Oyster Mushroom Outdoor Log Growing Kit

Description:

Italian Oysters (Pleurotus pulmonarius) are thicker and meatier than blue oyster mushrooms, and their brown frilled caps can grow quite large. They have a mild flavor, earthy aroma, and are favorite among those who prefer a sturdier oyster mushroom.

Oyster mushrooms are great for beginners because they colonize quickly and are reliable producers. 

FAQs

What type of log is best for growing mushrooms?

Some mushrooms are generalists, meaning they’ll grow on a wide variety of substrates, while others are specialists, preferring just a few. You can reference the chart below to find which tree species work best for each mushroom variety, and other types of wood they can be grown on. Preferred species will offer higher success rates, greater yields, and produce longer. Other types of wood can support mushroom growth but may have varying results in yield and length of production.

Most mushrooms grow on hardwoods, some species better than others. Generally, oak and maple perform well across the board. Their dense wood offers a lot of nutrition for a longer, sustained fruiting period. Softer hardwoods like poplar or aspen will myceliate faster and produce mushrooms sooner, but may not yield as much or produce for as many years. With that being said, oyster species love soft hardwoods like aspens and poplars!

Trees with more sapwood than heartwood may produce bigger flushes of mushrooms, especially in the case of shiitakes. Often, the sapwood section of a tree is thicker on trees with vigorous growth in open canopies rather than shade-grown trees.

What size should the logs be?

Any size logs will work. You can use branches or saplings, if that is what you have available. Small-diameter wood will colonize faster, but will not produce for as many seasons as a larger log. You don't want the logs to be so large or heavy that they are difficult to use. For drilling methods, a 4-6'' diameter with a 3-4' length is ideal. For the totem method, they can be up to a foot (or more!) in diameter, and 12-18'' high.

Should the wood be old or freshly cut?

Only freshly cut, disease-free wood should be used. Old or rotting wood should be avoided as it will likely contain contaminant fungi or be too dry to support mushroom growth. Once cut, the sooner you can inoculate the log the better, though you can wait up to 4 weeks after cutting before inoculating the log. When temperatures are consistently below freezing, the inoculation window can be extended for several months by covering freshly cut wood with snow to maintain moisture until you are ready to inoculate in early spring.

How often should I water my logs?

It’s important not to let the log dry out but it’s also important not to over-water the log. Logs should be stored in shady outdoor locations close to the ground. In temperate climates, they generally retain enough moisture to colonize fully without watering. During especially dry years, droughts, and in arid climates, watering may be necessary. Most of the time though, no supplemental watering is needed.

It’s okay to water the log to force it to fruit but most growers wait until the log fruits once naturally before beginning to shock them into fruiting. Logs shouldn’t stay wet on the outside for long periods of time. Frequent light watering can even damage logs and cause contaminant growth. Long periodic soaking is the preferred method of renewing water content should your logs appear dry or lose vitality.

Can I allow the log to freeze over winter?

Yes, logs will be fine in outdoors in the winter. A blanket of snow will help to protect the logs from drying out.

When should I inoculate my logs?

Logs should be inoculated within a week or two of cutting. This allows the cells in the tree to die but is not long enough for the log to dry out or for other competitor fungi to become established. You should not use logs that were cut last year or logs with damaged bark. A month would be about the longest reasonable stretch of time between cutting and inoculating.

What kind of yield can I expect?

The general rule of thumb is one year of production per inch of log diameter. However, yields will vary greatly depending on the mushroom strain, tree species used, and environmental conditions each season.

Shiitake logs usually have their largest flushes during their second and third years producing. A good yield per log is ¼ - ½ pound each flush, with 2-3 flushes per season.

How long will it take from the time of log inoculation to harvest?

That will depend on what species you’re growing, the size of your logs, and environmental conditions. Most mushrooms on standard size logs in temperate climates will take about a year to fully colonize before they fruit. This can vary between 6 months to two years. Smaller diameter logs and soft hardwoods will typically fruit sooner, though they’ll have less longevity.

Often, mushrooms need cool weather and moisture to fruit. Growth slows in the heat of the summer. If you inoculate in the spring, you might get your first flush of mushrooms in the fall but most likely it will take a full year until you see your first fruiting. If you inoculate in the fall and are able to keep the mycelium from going dormant, you may get mushrooms as soon as the next spring, though more likely the following fall.

What if I buy spawn and can't get around to inoculating right away?

Store the spawn in the fridge until you’re ready. We recommend waiting no more than a few months. Just be sure to inoculate your logs within 4 weeks of cutting them. We recommend avoiding log harvest in the spring between bud well and full-leaf out, since nutrients are directed toward flower and foliage growth and bark is loose. See our section about best time to harvest logs for more info.

Is my mushroom spawn moldy? What is the white or yellow substance?

Mushroom spawn will naturally develop a white (or yellow for Chicken of the Woods), mold-like layer called mycelium. This branching network of threads is the primary body of fungi, the vegetative structure. A good analogy is if a mushroom is like an apple, then mycelium is like an apple tree. Seeing mycelium grow through your bag is normal and indicates healthy mushroom spawn. If your spawn looks green or black, the culture may be contaminated and should be discarded. You can reach out to us for confirmation.

In the following images, you’ll see healthy spawn plugs with different amounts of mushroom culture visible. The first photo shows plugs with minimal mycelial growth. They are completely fine to use and not any less 'potent'. Over time the mycelium will continue to grow and envelop the plugs as seen in the second photograph. This is also normal and doesn't change how the plugs are used, though you may need to break up the plugs within the bag before use to separate them from the mycelial mass. Don't open the bag; simply squeeze it to break up the mycelial mass. The third photo is the same plug bag after it has been broken.

Often, mycelium is broken up in shipping, so it can appear less myceliated. Let it sit for a few days and it should bounce back.

What are the little dots in that I am seeing in my plug spawn bags?

Millet! We grow out our mushroom cultures on a mix of nutrient-rich grains to help them transfer onto wood. They are totally normal and can be ignored in your inoculation process.

Log inoculation

Healthy, living trees can be felled for mushroom logs nearly any time of year. It is not recommended to harvest logs during the spring between bud swell and full leaf out. During this time, most of the nutrients and energy of the tree are expended in a push to develop flowers and foliage, leaving little for fungal growth. Also, bark is loose, increasing the risk of damage during cutting. Intact bark is very important for the spawn run. Never cut dead, dying, or diseased trees for mushroom growing.

Log size

Any size logs will work. You can use branches or saplings, if that is what you have available. Small-diameter wood will colonize faster, but will not produce for as many seasons as a larger log. You don’t want the logs to be so large or heavy that they are difficult to use. For drilling methods, a 4-6’’ diameter with a 3-4’ length is ideal. For the pillar (aka totem) method, they can be up to a foot (or more!) in diameter, and 6-18’’ high.

We recommend sourcing logs from a sustainable forester or using sustainable practices in culling trees for mushroom production. For more information on selecting tree species for mushroom growing,
follow this link.

Methods of inoculation

There are two main methods of inoculating, the traditional log method and the pillar (aka totem) method. The traditional method works well for most mushrooms that grow on logs and can be adapted to use on stumps, too. We can trace its use back thousands of years to modern day Japan! The wonderful thing about mushroom logs is that you will get multiple years worth of gourmet mushrooms without having to re-inoculate your logs. On average, a mushroom log will produce for 1 year per inch of diameter of the log. So, if you inoculated a 5-inch diameter oak log with shiitake spawn, it will most likely produce for 5 years!

Timing your inoculation

Logs should be inoculated within a week or two of cutting. This allows the cells in the tree to die but is not long enough for the log to dry out or for other competitor fungi to become established. One month would be about the longest reasonable stretch of time between cutting and inoculating your logs. When temperatures are consistently below freezing, the window for inoculation can be extended for several months. Freshly cut wood can be covered with snow to maintain moisture until you are ready to inoculate in early spring.

Traditional log method

For drilling methods, a 4-6’’ diameter with a 3-4’ length is ideal.

Larger logs can be used but you don’t want the logs to be so heavy that they are difficult to move.

1. Use a 8.5mm or 5/16’’ bit for plug spawn or a 12mm or 7/16’’ bit for sawdust spawn and drill to a depth of 1’’ in a diamond pattern all over the perimeter of the log, omitting the cut ends. We recommend spacing holes four inches apart in rows that are staggered two inches apart.

2. Place plugs into your holes and use a hammer or mallet if the fit is snug. If using sawdust spawn, use an inoculation tool to push the sawdust spawn into the holes.

3. Brush melted wax over each plugged hole. We use a crockpot to melt the wax and a wool dauber or paint brush to apply it. The double boiler method can also be used. Sealing the holes is critical to success because it protects the spawn from drying out and from contamination. Keep in mind that it can be difficult to clean away the wax so allocating a thrift store crockpot or bowl to the job is a good idea.

Stump method

Stumps take longer than logs to colonize but can produce for up to a decade.

Any size stumps can be inoculated, but they should be from freshly cut trees. All inoculated stumps should be located in a shady environment. Make sure you can identify the stump and you know what species of tree it is!

1. Girdle your stump by removing a two inch wide band of bark, make sure to remove both the outer and inner layers of the bark. This helps to prevent suckers from growing.

2. Use a 8.5mm or 5/16’’ bit for plug spawn or a 12mm or 7/16’’ bit for sawdust spawn and drill to a depth of 1’’ all over the top, sides, and exposed roots of the stump.

3. Place plugs into your holes and use a hammer or mallet if the fit is snug. If using sawdust spawn use an inoculation tool to push sawdust spawn into the holes.

4. Brush melted wax over each plugged hole. We use a crockpot to melt the wax and a wool dauber or paint brush to apply it. The double boiler method can also be used. Sealing the holes is critical to success because it protects the spawn from drying out and from contamination. Keep in mind that it can be difficult to clean away the wax so allocating a thrift store crockpot or bowl to the job is a good idea.

Pillar (aka totem) method

In the pillar method, smaller sections of logs are stacked upright with sawdust spawn sandwiched between. No special tools are needed for this no-fuss technique and large-diameter wood becomes easy to use and attractive to display. This is the preferred method for oyster mushrooms, lion's mane, and reishi which naturally fruit when temperatures shift in the spring and fall. One 5lb bag of sawdust spawn should be enough to inoculate three or four 10-12" diameter stacks.

1. Cut three sections of log for each pillar: one piece only 2’’ long, and two sections 6’’ to 18’’ long.

2. Bring your supplies to your shady incubation place and create the pillars on site.

3. Lay a piece of brown cardboard or a kraft paper bag on the ground, sprinkle on a layer of sawdust spawn about 1’’ deep, and stand one of the 6’’-18’’ pieces upright on top of the spawn. Add another layer of sawdust spawn on top of this section and stand the next 6’’-18’’ section on top. Add one last layer of sawdust spawn on this section and then cap the pillar with the remaining 2’’ piece. Place an overturned paper lawn and leaf bag over your pillar. Tuck it under at the bottom or add weight to keep in place. The bag will help keep in moisture and keep out contaminants and pests.

4. Incubate the covered pillars for 4-12 months. When the logs are covered with a visible layer of mushroom mycelium (white mold-like substance) the paper bag can be removed. The pillar can be left intact or broken up into individual sections for fruiting.

Trenching or burying your logs

Burying or partially burying logs has been found to be critical to the successful fruiting of a few specific species. The advantages of burying or trenching these logs include additional moisture around the logs, beneficial microbes in the soil and triggers for fruit body development including light and oxygen limited to a smaller surface area.

We recommend burying or trenching hen of the woods, chicken of the woods, chestnut, nameko and reishi logs after full colonization. One way to check if your log is colonized is by looking for mycelium on the ends of your logs. Mycelium does not always cover the entire end but should be visible on most of the end, either on the surface or under the wax. If no mycelium is visible you can use the average colonization time of the species you selected. If in doubt we recommend waiting approximately one year in areas with snowy winters while those in areas with mild winters could trench their logs after three seasons have passed. Keep in mind larger diameter logs will take longer to colonize.

In order to trench your logs, dig out an area half as deep as the diameter of your logs in a shaded location. Reserve the soil you remove from this area. Place your logs in your dug trench in a raft formation. Then take your reserved soil and pack it around and between the logs so only the top surface area of the logs are exposed. For chestnut and nameko, wood chips or sawdust can be used in addition to or in place of soil. Water the area so the material around your logs compacts and add more if necessary!

Post inoculation

The time between inoculation and first harvest will depend on what species you’re growing, the size of your logs, and environmental conditions. Most mushrooms on standard size logs in temperate climates will take about a year to fully colonize before they fruit. This can vary between 6 months to two years. Smaller diameter logs and soft hardwoods will typically fruit sooner, though they’ll have less longevity.

Often, mushrooms need cool weather and moisture to fruit. Growth slows in the heat of the summer. If you inoculate in the spring, you might get your first flush of mushrooms in the fall but most likely it will take a full year until you see your first fruiting. If you inoculate in the fall and are able to keep the mycelium from going dormant, you may get mushrooms as soon as the next spring, though more likely the following fall.

Mushroom log yields depend on the type of wood chosen, the species you are inoculating, and environmental conditions. Generally speaking, dense hardwoods take longer to fully colonize but will continue to fruit for more years, while soft hardwoods (like poplar) will fruit sooner for fewer years. And wood with more sapwood than heartwood may yield more mushrooms.

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Maintenance and fruiting

Incubate logs in a shady place, close to the forest floor but not in contact with soil or leaf litter. Lay down tracks of scrap wood that elevate the logs 1-2'' above the forest floor. Stack the logs in a layer with a little space for airflow between each log. If you have more logs, you can make multiple layers by off-setting each layer by 90°. Keep the stack lower than the average snow line, as the snow cover protects the logs from dry winter winds.

Generally, no special care is needed while the mycelium grows throughout the log, but watering may be needed if excessively dry weather occurs. Logs shouldn’t stay wet on the outside for long periods of time. Frequent light watering can even damage logs and cause contaminant growth. Long periodic soaking of no more than 24 hours is the preferred method of renewing water content should your logs appear dry or lose vitality.

Restack the logs into a log cabin fashion for increased airflow and ease of mushroom picking, about a year after inoculation. Log cabin stacks can be as high as 5' in wetter climates but in dry climates shorter stacks, closer to the ground, help keep logs moist.

Fruiting naturally occurs after rains and occurs in cycles. After the log has fruited once on its own, it can be stimulated to fruit by watering or soaking it in cold water for no more than 24 hours. Force fruiting works best with shiitake mushrooms. Allow at least one month of rest before attempting to force fruit again. If it has recently fruited, forcing will probably not work.