In June 2021, POP Orchard Intern Simone Shemshedini hosted a mushroom inoculation workshop at Philadelphia Orchard Project’s Learning Orchard as a part of POP’s First Thursdays Workshop Series. A full house of both fungi amateurs and experts came to enjoy the beauty of the orchard while sharing skills and knowledge. Shemshedini quickly brought everyone at the workshop into the world of fungi with this highly interactive workshop. She guided us in the craft of creating oyster mushroom grow bags and inoculating logs with shiitake plugs. 

Simone Shemshedini demonstrates how to inoculate logs with shiitake plugs. Photo credit: Tirzah Vogels.

Ecological Significance

Fungi play a major role as decomposers and recyclers in a wide variety of habitats. The food web is incomplete without organisms that decompose organic matter. 

Fungi are valuable because they replenish the environment with essential elements and nutrients. By breaking down organic matter, they recycle nutrients by returning them into the soil. Many elements that are essential for biological systems are not bioavailable and fungi are able to release these elements from decaying matter. 

Many fungi have a symbiosis with plants – the fungus helps the tree extract water and nutrients while the tree supplies the fungus with sugars. Most plant species depend heavily on fungi for their survival. 

Vocabulary

Fungi: spore producing organisms that feed on decaying organic matter

Mushroom: fruiting bodies of the fungi that typically grow above the ground and the part we eat

Mycelium: the main body of the fungus that functions as the “roots’ of the fungi, absorbing water and nutrients

Spores: the “seeds” of the fungi that allow fungi to reproduce

Mold: type of fungus that grows as a thread-like structure, that can cause food spoilage but also plays a role in the production of certain foods, beverages, and antibiotics

Inoculation: Introducing a mushroom spawn to a planting substrate

Spawn: A carrier that holds mycelium. Used to grow mushrooms. 

How to grow mushroom in Grow Bag

Workshop attendees fill their grow bags with a substrate of spent coffee grounds and shredded paper. Photo credit: Tirzah Vogels.
Workshop attendees fill their grow bags with a substrate of spent coffee grounds and shredded paper. Photo credit: Tirzah Vogels.

Materials needed:

  1. Substrate (spent coffee grounds, straw, shredded paper, coconut coir).
  2. Mushroom spawn (oyster mushrooms are the easiest). Field and Forest is a great place for ordering spawn
  3. Plastic mushroom grow bag or gallon size freezer ziplock bag

Instructions

  1. Make sure all of the substrate is sterile. Spent coffee grounds are already sterilized (from pouring boiling water over the grounds), but shredded paper needs to be boiled for 1 hour then drained and squeezed out. Should still be moist but not dripping.
  2. Put on gloves to keep things sterile. Fill bag with a scoop of spent coffee grounds, a bigger scoop of shredded paper, and a small scoop of spawn and seal bag with tape. Shake bag until fully incorporated.
  3. Let your spores sprout! Place bag in a warm and dark spot. After approximately 3 weeks, mycelium (white, thread-like filaments) should be fully incorporated into substrate.
  4. Let it fruit! Now it’s time to place bag in an area with indirect light. Cut a few 3 inch horizontal slits on bag for air flow and to allow mushrooms to pop out of bag. Water lightly twice daily (a water sprayer is best). In about a week, mushrooms should appear. Cut at base when ready.

Troubleshooting

If there is mold growing in your bag, it means mold spores got in your bag. If the patch is small, you can sprinkle salt directly on the mold or scoop it out with a sterile spoon. This should kill the mold while not harming the mycelium. If there is a lot of mold, you will likely need to start over with new spawn and substrate. 

Precautions

To prevent this from happening, make sure to wash your hands when making your bag. Keep bag moist, but don’t oversaturate it. Lastly, make sure to cut the slits after three weeks to allow for air flow. 

If there is mold growing in your bag, it means mold spores got in your bag. If the patch is small, you can sprinkle salt directly on the mold or scoop it out with a sterile spoon. This should kill the mold while not harming the mycelium. If there is a lot of mold, you will likely need to start over with new spawn and substrate. 

How to grow Shitake Mushrooms on a log. 

Supplies needed for inoculating a mushroom log.  Photo credit: Tirzah Vogels.
Supplies needed for inoculating a mushroom log. Photo credit: Tirzah Vogels.

Materials Needed.

  1. Hardwood logs. Oak is the gold standard, but American Beech, Sugar Maple, and Alder are all great options. 3-4 feet long. 3-8” in diameter. No older than 2 months from time of cutting/wind fall. Winter and spring cut logs have highest success rate. 
  2. Shitake plug spawn (mycelium grown into hardwood dowels).
  3. 5/16” drill bit and drill
  4. Hammer
  5. Plug Wax (easiest), cheese wax, or beeswax. 
  6. Gloves

Instructions. Drill and Fill Inoculation Method.

  1. Before inoculation, logs should be kept in shade but where they will receive rainfall/can be watered regularly. 
  2. Drill 5/16” holes 1.25” deep in log. Drill in staggered rows: 6” in row, 2” between each row. 
  3. Place plug spawn into holes and gently tap in with hammer until flush with wood
  4. Seal with wax. Plug wax does not need to be melted and can be applied easily with gloved hand or spoon. Cheese wax and beeswax need to be melted and applied while hot. 
Log with shiitake plugs ready to be tapped in and sealed with wax. Photo credit: Tirzah Vogels.

What to do with mushroom bounty?

Preparing: Brush off any substrate and dirt from mushrooms; do not immerse in water! For stubborn dirt, use a damp paper or kitchen towel.

Cooking: 

  1. Sauté with butter.
  2. Cover in breadcrumbs and fry in oil.
  3. Make mushroom burgers.

Preserving:

Dehydrate! Lay on drying rack in area with good air circulation and let mushrooms dry for a few days. Or, consider using the oven or a dehydrator, as described here.

This blog post was written by POP Education & Outreach Coordinator Corrie Spellman-Lopez.

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