Cutting and Care
Logs, it is best to cut logs from Autumn to early Spring, before bud-break, however logs cut in the summer also work well. After cutting keep in the shade, you can inoculate immediately, after 6 weeks from cutting the risk of colonization by wild fungi is greater,
Logs for Shiitake are best between 10 to 20cm in diameter, this gives a good ratio of sap wood to heart wood. The length of your log should not be to short to prevent drying out, between 50cm to 1m is a good size to handle and also not to big to sock in a container full of water. For big mushrooms like Chicken of the Woods you need a big log up to 1m diameter by 2m long which can be left lying on the ground or part buried like a stump.
Type of logs
Wood Density, Higher wood density means more lignin which the fungi feed on. Low density softer hardwoods like Willow will grow good mushrooms but produce less that say a Beech log of the same size.
Sapwood to Heartwood Ratio, The sapwood is the living outer ring of wood under the bark which is more favorable for colonization by fungus. The darker heartwood is indigestible to for example shiitake fungus. Scottish oak grows very slowly and so has little sapwood. West coast English and Welsh Oak is much preferred.
Bark is one of the most critical factors in successful mushroom production. The logs really have to be manually handled out of the wood to prevent any damage to the bark. The bark controls moisture loss from the log, tree spp. with thicker bark dry out more slowly. Logs cut in late spring when the sapwood is expanding have loose / softer bark which can dry out, crack and fall off the log causing the log to dry out. The same log cut earlier in the winter rather than spring is less likely to have the bark problems.