Mushroom Logs -The Stuffing Method (No Dowels!) October 06, 2015 06:00 1 Comment

Last week, we were honored to have mushroom cultivator, soil enthusiast, and permaculture food producer Danielle Stevenson of D.I.Y Fungi in to teach a 3 day mushroom cultivation course/workshop series. She focused on low-tech skills to grow mushrooms from easy to access materials - like grains, straw, cardboard, and household waste - to teach folks how they can grow mushrooms all year around.

Danielle's Palm Inoculator

For Sunday's outdoor mushroom cultivation workshop, we learned some low-tech skills to grow mushrooms outside. She showed us an alternative method to growing mushrooms out of logs that doesn't require dowels (log-specific mushroom plugs that can be harder to access and more expensive to purchase).   

So before I go into it, here are some things you'll need:

-Fresh hardwood logs: between 2 weeks and 3 months old and 4"-6" in diameter. If they have been felled for less than two weeks, your log may still be acting as if it were alive and push out fungi or bacteria. If it's older than 3 months, it is very likely that it is already populated with too many bacteria, fungi, and and/or mold to compete with. Different mushroom species prefer different food sources (just like people), so it's a good practice to look up which tree species work best with the mushroom you want to grow. We used oak for reishi and shiitake, plum for reishi, and cottonwood for oyster - all of which we scavenged from the windstorm last month. Alder and Maple are also really great hardwoods that works for many species. 

-Spawn: You can use several types fairly mature mushroom spawn that works with the logs you have (if it's fully eaten it's food and the spawn bag is looking pretty white with mycelium, it will be totally fine to transfer to a new substrate - aka food). Like people, fungi like diversity in their diet and don't like to eat the same thing all the time. It's good to change up its food sources. So if you have some fungi growing on and eating coffee grounds, bits of straw, sawdust - anything other than grain spawn, which will attract rats and pests (yum, it's pretty much tempeh!) - as long as you can get bits of it to fit into small pinky sized holes you're probably good to go.

-Alcohol OR Hand Sanitizer: It's really important to remember we have TONS of living organisms we can't see on our hands. These little guys can be a real burden to the fungi we want to grow for food and medicine, so it's really important we keep our hands sanitized. A cheap way to do this is to keep rubbing alcohol in a spray bottle, which you can then use for your hands, plus any other surfaces that you or your fungal friends might come into contact with. On this note, it's important to remember we also have a ton of micro-buddies living in our mouths, and so it's best to practice not to be breathing into your bags of spawn, or talking too much while handling your spawn. 

-Palm Inoculator OR Nitrile Gloves (Optional): You can get a palm inoculator online for about $40-50. It essentially sucks up the sawdust spawn and then you can pop it right into the holes in the logs in a more sanitary way (rather than using your hands which is touching everything from the spawn bag to the logs themselves). However, you can also experiment with just using nitrile gloves, or really good sanitizing practices - keeping your hands really clean and avoiding touching too many surfaces.

-Drill: You want a pretty powerful drill with good battery life, or a really long extension cord. The bit size should be on the bigger size, about the size of a pinky finger (like a pinky finger, the size doesn't need to be exact). 

-Beeswax + Pot + Stove: You want to melt some beeswax to seal and protect your logs from other microorganisms that may out-compete your fungi culture. 

-Sponge, Paintbrush OR cardboard: To brush beeswax onto your log with

-Big Piece of Cardboard: For your finished log to sit on. Some mushrooms species we grow are native to this climate, like the oyster mushroom pleurotus ostreatus. But some species we want to grow for food and medicine are not from here and are don't connect well with other bacteria and fungi. So to lessen your odds of contamination, you can put your log(s) on a piece of cardboard. 

-Friends! This method is easiest to do when there are at least 3 people working together. 1 person to drill, 1 person to plug, and 1 person to follow with the beeswax.


 The Steps:

1. Drill Holes: Again, these should be about the size of your pinky, and two knuckles deep. You can wrap tape around your drill bit to mark the maximum depth you want to drill into (a drill stop).  Drill holes about 1 to 1 and a half fist distances apart all along the log on all sides of the log. The holes can be drilled in a diamond or checkered pattern.Drilling Mushroom Holes

2. Stuff Holes with Mushroom Spawn: One of the benefits of sawdust, grain, or coffee ground spawn is that they have a higher ratios of mycelium than a dowel plug which may increase your chances of success. Spray alcohol on to your palm inoculator, hands, and/or whatever makeshift items you can think of (we tried stuffing small funnels to insert into the drill holes, and then poking the spawn out with a stick. We also tried using a large modified syringe. Neither worked as well as using our hands.) Carefully stuff the holes with spawn. If you are using multiple mushroom species and/or cultures, remember to disinfect your hands and tools before moving on to a new species. Different strains of mushroom cultures will also have a tough (nearly impossible?) time growing on the same food source - even if they are the species.

Stuffing Logs with Sawdust Spawn

3. Seal with Beeswax: While your friends are drilling and stuffing, melt some beeswax in a pot. Some folks say to use a double boiler to avoid burning the wax, but you can use a single pot as long as you are mindful of the temperature. When the wax is melted, use either a sponge, paint brush, or some cardboard to seal the already stuffed holes with beeswax. This will help keep competitors out. On this note, it is also important to seal off any major exposed wounds or scrapes on your log where bark has been torn away. Dipping Into the Beeswax

4. Seal the Base of the Log with Beeswax: After all of the holes have been drilled, stuffed, and sealed, seal the end of your log by dipping it into your pot of beeswax. Only seal off one end so moisture can still get in. The unsealed end will also be an indicator of successful myceliation in the future.

4. Place your logs!

For Shiitake and Oyster Logs: The logs are best placed outside in a  shady and naturally moist location. Logs can be placed horizontally on pallets, cinder blocks or even cardboard if it's all you have, off the ground to prevent competition from soil dwelling fungi. 6-9 months after inoculation, you should see white at the ends of the logs. Once you see this, you can stack them "log cabin" style for fruiting.

Lion's Mane and Maitake: After 6-9 months, once you see white at the ends of the logs, bury about a quarter to a third way upright in the soil in a shady moist location.

For Reishi: Bury upright in sand in a black planter pot. Reishi like more heat and does well in greenhouses. Just make sure they don't dry out!

Buried Logs (done with Fungi for the People in Oregon)

(Some fungi are social and like to interact with native soil dwelling species. In some of these cases one option is to semi-bury your logs)

5. Many Days of Moisture: Just like humans, mushrooms are made up mostly of water so it's very important after inoculation to keep your logs moist! Water 2-3 times a week and do not let them dry out. It takes about 6 months to a year for mushrooms to fruit for Shiitake, Oyster and Lion's Mane, Maitake and reishi can take even longer, so it's really important not to forget about your logs during this process and make sure they maintain moisture.

6. Grow Mushrooms! If all goes well, watch your mushrooms fruit! If you can see mycelium (that white stuff growing in a net-like pattern) growing at the end of your log, and the timing is right according to the mushroom (blue oyster is winter fruiting for example), but still no signs of fruiting mushrooms, soak your logs! You can force fruit logs by completely soaking them in water for 12-24 hours every five weeks. Your logs should produce for about 1 year per inch in diameter (so about 4-6 years). Shiitake and oyster will fruit multiple times a year, and Lion's Mane about once a year. 

Enjoy y'all! And thanks Danielle for the tips! 


by Kelsey Cham Corbett
October 6th, 2016