In Japan the different grades of shiitake are called Donko, Koko and Koshin. They are considered more potent in terms of their antiviral and immune-boosting qualities. This grade is associated with warm weather strains growing in warmer temperatures and high humidity. Koko grade mushrooms are intermediate between Koshin and Donko, having medium thick flesh and partially open caps. Trees should be felled when the leaves are off, and logs should be inoculated as soon as possible, certainly within 3 weeks.
Moisture is everything.
You should maintain the internal moisture content of fresh cut logs at 45 to 60 percent after inoculation. This is simply accomplished by exposing the logs to rainfall and periodic soaking with a sprinkler, avoiding wind and strong sunlight, and stacking the logs in an appropriate way. Detailed instructions can be found in these pages, but also we urge serious growers to purchase a book or videotape to learn the finer points of cultivating mushrooms. For commercial operations this translates to maximizing profits. But to assure shipment in time for your inoculation, please place your order at least 6 weeks in advance.