Fresh logs can be inoculated with mushroom mycelium using wooden plugs or with so-called grain spawn. The mycelium then grows into the log and spreads itself out. Inoculated plugs are actually normal wooden dowels which had been sterilized and then inoculated with mushroom mycelium.
It's easy to put the plugs into the logs, all you need to do is drill holes and bang in the plugs using a hammer. It's a bit more tricky to put the grain spawn into the logs. You first need to cut slots with a chainsaw or drill large diameter holes. The grain spawn is then filled into the slots or holes using a funnel or spoon. You must seal up the slots or holes again to ensure that the loose grain spawn doesn't fall out again.
You now need patience while the mushroom mycelium penetrates the wood. During this phase the log should be stored for several months wrapped in a plastic foil either in the garden or indoors.
The photo below shows a slot containing grain spawn which has being sealed up with packing tape. The log has already been stored for a while and the white mycelium has even grown out from underneath the packing tape.
The photo below shows logs inoculated with oyster mushrooms. You can recognize mature inoculated logs by the appearance of white mycelium at the cut end of the log (the mycelium is cream or brown in the case of shiitake mushrooms.
The log should now be taken to the intended growing place in the garden. The short thick logs you use e.g. for oyster mushroom should be buried in the soil by about one third, as shown in the photo. Shiitake logs should not be buried but instead lent against a fence or the tree. Take note: all mushroom logs need occasional rainwater so don't put them under a tree with thick vegetation or under a roof. After a while you should be able to harvest fresh mushrooms from the log several times a year.
Click the following link and then click on Wood types for information of on which wood is best for which mushroom type. Growing instructions >