I'm going to share a recent discovery I made...
This year I've been experimenting with incorporating mycelium into sheet mulch. The ground is frozen for about 6 months of the year, and I've noticed things decay slowly, compost takes forever to finish off etc.
I've been adding organic matter to my soil, so I'm looking to sheet mulch not only to suppress unwanted vegetation, but also as a means of composting in place. I got some spent grow logs and I've been building sheet mulch using different combinations of newspaper, hay, straw, used coffee grounds, and the grow logs sliced into discs.
I'm using between 5 and 15 gallons of used coffee grounds per log by the way.
I noticed an explosion in the slug population which is par for the course in sheet mulching. But they don't eat my plants. It appears their preferred food is the wet newspaper. I've been observing these slugs on a regular basis. They tend to leave the mycelium alone, and they avoid the used coffee grounds.
In the beds where the mycelium is covered by a thin layer of newspaper I discovered a neat dynamic. The slugs graze on the newspaper but not in a random fashion. They tend to eat the newspaper in spots until they eat right through, and then they move on to a fresh area. So I'm seeing fissures appear in the newspaper. These fissures in turn are allowing oxygen into the sub layer of mycelium and used coffee grounds, and the mycelium react by fruiting up through these holes.
Rather than having an explosion of mushrooms in my garden beds everywhere and all at once like I was expecting, I'm getting a controlled production thanks to my little workers.