Much care goes into producing our log-grown mushrooms and log kits. Journey with us from harvesting logs in the winter to harvesting mushrooms the following year.
The first step is harvesting green (live) winter-cut logs. For the last few years we’ve been able to cut these logs ourselves, helping land-owners thin their woods and do forest management, rather than clear-cutting. We cut mostly oak, but also aspen and poplar, depending on the kinds of mushrooms we intend to grow. For log-grown mushrooms, the logs must be cut in the winter when all the sap is inside the trunk of the tree – not out in the branches working to make leaves.
Log inoculation in our fruiting house (greenhouse)
We also need spawn (the mushroom organism growing on sawdust), caps, and drill bits. Each log is drilled with between 50 and 150 holes, each hole is packed with spawn, then sealed with a cap that holds in moisture. Logs that have been inoculated are piled up in the fruiting house in dense covered stacks until we get a chance (or the weather allows!) to move them to the incubation area.
Here’s a video of inoculations from a few years ago, but you can find out more about our new approach here!
The incubating area
For incubation or “spawn run,” we lay out the logs close to the ground in a shady area. In the past this has been a wooded area on the farm, but we are now incubating logs under a shade structure – a pipe structure that supports a porous tarp – next to our older logs.
Spawn run is the period when the mushroom organism, or mycelium, spreads throughout the logs. Incubation typically takes 3 to 12 months depending on the mushroom variety, environment, and quality of materials. In our climate there is very little we have to do with these logs to encourage them, other than watering them during the occasional dry spell.
The log resting area
After mushrooms start to fruit on the logs, we move them over to the resting area. This generally happens in the fall. Our resting area is a shade structure. The logs need protection from sun and wind, and the structure helps with this, while allowing us easy access to the logs. If the conditions are right, these new logs will fruit naturally in the shade structure during the fall. As winter approaches, we cover all the stacks of logs with shade fabric and they go dormant until the weather warms up the following year.
Force-fruiting – soaking
In the summer, we start force-fruiting the logs that were inoculated the previous year (as well as all the older logs). Some varieties of shiitake respond to force-fruiting (prolonged soaking in cold water) by fruiting prolifically. They are reacting to changes in moisture and temperature. Each week we remove logs from the resting area and soak them in fresh water for about a day.
Force-fruiting – mushroom growth in fruiting house
The next day we remove the logs from the water and move them to the fruiting house where they will fruit within the next week or so. Once all the mushrooms are picked, we move the logs back to the resting area and bring in a new batch to fruit the following week.
Not all shiitake growers use a fruiting house, but the most consistent high-quality shiitake are grown this way, since we are able to control humidity, air movement, and even temperature much more than in an outdoor fruiting area. With the help of many of you we raised the funds for our first fruiting house – through a Kickstarter campaign. Thank you supporters!