How Long do Shiitake Logs Last?
Shiitake are, by far, our favorite type of mushrooms to grow on logs. Logs generally last anywhere between 4 to 6 years, but there are a few factors to keep in mind.
First and foremost is the diameter of the logs. In general terms we expect a shiitake mushroom log to last one year per inch in diameter; meaning a 4 inch diameter logs should last for 4 years, an 8 inch diameter log should last for 8 years, etc. This does change, however, if you are force-fruiting your logs. If you opt to force-fruit logs you are expediting the decomposition of the logs, ultimately leading to a shorten lifespan. Another way to think about it is- a shiitake log can produce about 12 crops. These crops come on naturally in the spring and fall, bring the average production lifespan to 6 years. However, if you're vigorously force-fruiting your logs (even twice per year) that would equal 4 fruiting per year, bringing the log's lifespan down to 3 years. As always with fungi, there will be some variation based on your fruiting environment and methods.
If growing shiitake on logs for market production, strain matters. Wide Range strains (such as WR46) are often the first choice of commercial growers for their fast spawn run and productivity. While we also recommend starting with Wide Range strains we do notice a decline in mushroom quality as the log ages, particularly with WR46 and West Wind (and to a lesser extent Double Jewel and Beltane). In the photos above you can see the quality difference in a shiitake from a log in its first year and then in its 5th year. As the log ages the mushrooms have to work harder to break down macromolecules for food, resulting in mushrooms that are both small in cap diameter and cap thickness.
Warm weather and cool weather strains are less prone to reduction in mushroom quality as the logs age. The mycelium in these strains is less aggressive, and therefore the movement underneath the bark's surface is less drastic and impactful. A slower moving mycelium will be gentler on the bark, allowing for mushrooms to form in a more protected environment.
It is important to note when it comes to mushroom quality that the overall yield remains about the same. It's more a matter of many small mushrooms or fewer, higher quality mushrooms.
Shiitake Mushroom Logs:
Generally 4-6 Years
Oyster Mushroom Logs:
2-3 Years
Other Mushroom Logs:
Dependent on wood type and mushroom species
Note:**
There are many variables when it comes to judging how long a mushroom log will produce. Please take the timelines in this blogs as guidelines, not rules.
How Long do Oyster Logs Last?
Oyster mushroom logs are shorter-lived than shiitake mushroom logs. Shiitake grow on hard hardwoods such as oak and sugar maple while oysters grow on the softer hardwoods like box elder, cottonwood, poplar, etc. The softer woods just decompose quicker, leading to a shorter mushroom log lifespan.
Other Specialty Mushroom Logs
Other specialty mushroom logs such as Chestnut, Lion's Mane, Turkey Tail, etc. will range in lifespan largely based on which wood species is used as well as the mushroom variety. For example, Lion's Mane will last much longer on oak than it will on birch just because of bark composition. Generally Lion's Mane will last as long as shiitake, but will be less productive. Fungi like Chestnut and, to an even greater extent, Turkey Tail aggressively eat through logs and generally last only 2 to 3 years.
