Can I Grow Mushrooms on Wood that Comes Down in Summer?

Yes, you can! While inoculating trees downed in the summer is not usually recommended it can, in fact, yield a respectable amount of mushrooms. While we still would not suggest going out of your way to cut and use trees during the summer, if you have a tree come down in a storm, why not make the most of it? The following guidelines will help you turn the tables towards pounds of mushrooms rather than bundles of firewood and help you get the most out of your inoculation efforts this summer.

oak tree that came down in May
wilted leaves
Shiitake mushrooms on log

Plan to take advantage of wood made available through sudden acts of Mother Nature.

Wood that comes down as a result of summer storms is often from very healthy branches or whole trees which are great candidates for mushroom cultivation. If you can organize your growing supplies ahead of time you can take advantage of this sometimes plentiful (and free) wood source.

Wood should be inoculated right after the leaves on the branch show signs of wilt, so have your supplies ready.

During the summer, growth and cell division within the tree's physiology is very active. Nutrition manufactured by the leaves moves into the branches, trunk and roots, supporting growth while sap courses through the tree causing the moisture content of the wood, especially in the inner bark, to be very high. When wood is cut in the summer, it loses this abundance of moisture rapidly, leaving the bark loose and easy to peel away. Handle your logs carefully, because once the bark peels off the logs they are more prone to drying out and contamination. Wilting of the leaves on the downed branch of trunk indicates the rapid loss of water and that inoculation time is at hand! Loss of water and vitality is slow at first. The leaves on the downed branch look bright and turgid at first, but depending on wood species and geographic location seem to show signs of wilt almost overnight or within just a few days. Leaves on a pin oak that came down at our farm on May 25 looked as you would expect them to look on a living tree, then suddenly wilted overnight on May 28, just 3 days later. You can wait until several weeks later to inoculate but the best success is with quick inoculation.

Adjust your expectations of how the logs should look after the first fruiting.

Summer downed and inoculated mushroom wood looks great up through the first fruiting, but depending on how strict you are with following the above guidelines, can look a little, well, ratty after the first fruiting or two. The logs will continue fruiting and will last longer if you avoid a lot of handling, such as forced fruiting.

In summary:

If you are willing to act quickly, you can use an unexpected supply of good quality wood to make a good quality mushroom log. Spawn purchased for this purpose, especially Plug spawn, can be stored in the refrigerator for months and can be used for a fall inoculation if you don't use it this summer. While summer inoculated logs tend to last only 2-3 years the best yields are often harvested in the first few flushes, you will still see good value in conversion of wood to mushrooms. You'll be glad you made the effort to turn the disappointment of downed wood to a gift. Have a great summer!


Time to plant:
Typically spring, but throughout the growing season if trees fall down.
Time to fruiting:
Plug spawn: 9-18 months; sawdust spawn: 5-12 months (larger diameter logs take longer than smaller diameter logs).
When they fruit:
Spring through fall, depending on strain.
Logs grown on:
Hardwoods, ideally Oak species, Sugar Maple, and Ironwood.
Number of logs:
Depends on log size (ideal is 4-6˝ diameter x 36-40˝ long). Plug spawn: approximately 50 plugs per log. Sawdust spawn: 10-12 logs (2.5 lb. bag) or 20-25 logs (5.5 lb. bag).