Recommended wood types for growing edible mushrooms and spawn quantity

If you want to inoculate logs with mushroom spawn, please check the table at the bottom of this page with our recommendations for wood types.

The best wood type for shii-take is oak. In the case of northern red oak (Quercus rubra), it is better if the logs are slightly thicker because with thinner logs the amount of sapwood, which is important for the mushrooms, is very small.You cannot use wood from conifers.

Spawn quantity:

• Inoculated plugs: Logs of about 35 – 40 cm in length and 18 - 20 cm in diameter need 12 to 15 plugs. Thinner logs for shiitake (diameter 10 to max. 15 cm) need 12 to 15 plugs per meter of log.
• Grain spawn: One litre of grain spawn is enough to inoculate about 6 logs of approx. 35 – 40 cm in length and 20 cm in diameter.
  With thinner logs for shiitake, one litre of grain spawn is enough for 6 logs (diameter 10 to 15 cm, length 120 cm).
• If you increase the number of plugs or quantity of grain spawn, this shortens the time need for the mycelia propagation phase.

Wood quality: Important!

Living trees have a built in defence system against fungus growth. The logs must be stored for at least four weeks after felling the tree to ensure that the defence system is no longer active. Try to prevent the logs from drying out during this time. If necessary, you can water them carefully before inoculation.
When you carry out inoculation, it is important that the logs are still moist and that they have not been infested by foreign fungi in the meantime. Accordingly, you should not store them for longer than three months after felling the tree and they should appear healthy. They should not be split or have the bark removed.

Best time of year for inoculation

In general, you can inoculate logs at any time during the year, but they should be protected from heavy frosts during the propagation phase, above all during the first 6 weeks.
Spring is an ideal time to inoculate, among other things due to availabilty of fresh wood from winter logging activities.

In the table below, diameter and length are approximate values.