Mushroom Log Inoculation

Log cultivation is usually done with logs 4 to 6 inches in diameter with a length of 3 to 4 feet. Oak is particularly good for the cultivation of most mushrooms though many other hardwoods work well also, such as poplar, aspen, sugar maple, willow, alder and birch, among others. Conifers are to be avoided for the cultivation of most mushrooms with the exception of chicken of the woods. To select the appropriate trees for the cultivation of different gourmet mushrooms, refer to the tree selection guide on the back of this sheet. The best times for cutting logs are either in the winter months for spring inoculation or from August through October for late summer or fall inoculation. When inoculating logs in the summer, it is best to do the inoculation in the morning in a shady place. When selecting logs for mushroom cultivation, choose living trees without signs of decay. If the tree is dead, it will certainly already have other fungi growing in the wood. Using logs from a dead or unhealthy tree will either lower your yields or prevent production altogether. It is best to inoculate logs in early spring if they have been cut during the winter. You can usually begin to inoculate logs one month before the average last frost date as long as day-time temperatures are above 40o F. If you cut logs during summer, it is best to inoculate them within 3 weeks after they have been cut so that the logs will still have an adequate moisture content. After inoculation, the logs are placed in a shady location out of the wind. Logs generally begin producing 6 months to 1 year after inoculation; after which, they usually continue to fruit for 4 years producing 1-2 lb. per year. Each log usually produces 2.5 lb - 4 lb over its lifetime. Reishi, chicken of the woods, maitake and oyster grow well on both logs and stumps. For inoculation, you will need a drill, a hammer and cheesewax. If you are using plug spawn, you will need a 5/16 in. drill bit. If you are using sawdust spawn, you will need a 7/16 in. drill bit. Spawn can stay viable for up to 6 months in a refrigerator. For all your log inoculation needs, please visit our log cultivation supplies page.

Step 1

Drill 1 in. deep holes for plug spawn or 1 in. deep holes for sawdust spawn into the log spacing the holes about 6 - 8 in. apart within a row. Leave approximately 2 in. between the rows and offset the holes so that they form a hexagonal pattern. A 4 in. diameter log will need 6 rows; a 5 in. diameter log will need 7, and a 6 in. diameter log will need 9 rows. A 4 in. log usually is given about 40 - 50 plugs. A large stump usually requires 100 to 200 holes arranged in a similar hexagonal fashion around the trunk and with holes on the top of the stump as well. Spawn for all mushroom varieties are inoculated into logs and stumps in this manner.

Step 2

If using plug spawn, hammer the plugs into the holes flush with the bark. If using sawdust spawn, plunge the inoculator into the sawdust and then insert the spawn into the holes. Make sure the sawdust spawn is packed tightly into the hole flush with the bark.

Step 3

Cover the plugs or sawdust with cheesewax. To do this, melt the wax in a pan which can be maintained at 300oF. An electric frying pan with a thermostat control works well for this. If inoculating away from electricity, using a camp stove, make sure that the wax is hot when you apply it; otherwise, the wax will not create a tight seal and can easily fall off. The cheesewax will smoke lightly when it is adequately hot. The wax can be applied with a foam brush or dauber.

Step 4

Choose a shady location which receives protection from the wind. Shiitake, woodears, oyster, and lion's mane are usually grown on logs that are leaned against a rail, fence or other similar structure. You can also bury of the log so that it is standing upright or lay the logs on the ground. For maitake and chicken of the woods, bury the logs halfway standing upright. For reishi either lay the logs on the ground or bury the logs length-wise just under the soil surface for enhanced moisture. Larger diameter logs of reishi in 2 ft lengths can be buried halfway standing upright as a stump.

Log Maintenance

It is very important to take care of your logs while they are colonizing or resting in between fruitings. The easiest way to help with keeping your logs heathy and happy is to cover them with a tarp to keep them out of direct sunlight and to keep the humidity in. Check on your logs regularly to ensure that they are moist. If your logs ever seem dry, water them. Although they obtain their nuttrients differntly from plants, your mushrooms need water to stay alive just like plants.

Tree Selection Guide


The logs that will produce the highest yields of shiitake are oaks, chestnut and ironwood. Many other species will produce yields that are still satisfactory though not quite as high, such as sweetgum, bitternut hickory, alder, aspen, hard maples (sugar and black), black willow, yellow birch and river birch. Trees to avoid for shiitake cultivation include conifers, fruit trees, elm, hackberry, sassafras, soft maples (red and striped), sourwood, tulip poplar, dogwood, black locust, beech and most of the hickories.


Will grow on a wide range of hardwood logs and some conifers: oak, elm, maple, sycamore, beech, plum, peach, hemlock, mimosa, and many others.


These mushrooms prefer tulip poplar, aspen, cottonwood, beech, willow, maple and sweetgum.


Consider growing on large diameter oak stumps or large diameter oak logs 2 ft. in length that are buried half-way standing upright to create a stump.

Chicken of the Woods

Like Maitake, these can be grown on large diameter stumps or large diameter logs 2 ft. in length that are buried half-way standing upright. It will also grow on large diameter logs laying on the ground, such as fallen tree trunks and butt logs. Chicken of the woods grows well on oak, spruce, fir and hemlock.

Lion's Mane

This mushroom will grow on a wide range of hardwoods, including oak, walnut, beech, and elm.

Wood Ears

Enjoys growing on a wide range of hardwoods, including oak and many others.


Best on birch trees.

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