This is a cool technique that I read about on Rodale's website, I've been wanting to try it for years.
Another technique that I do use, but I don't know that it actually spreads mycorhizae, is coloquially called 'fungal flats'. I have been told that it actually cultures actinomycetes, but in any case it seems to make plants happy. The recipe is as follolws:
2 parts high quality compost 1 part high humate soils (alaska humisoil is a nationally available brand)
1 part worm castings
1/8 part humic acid
1/8 part oceanic hydrolysate
you mix the ingredients all together and then cover in a high humidity situation for 3-7 days. the medium will become covered with white fuzz and can be used to innoculate transplant holes, add to compost teas, or spread under mulch as a top dress.
I typically use 2 cups as a 'part' in the above recipe and put the resulting ~8 cup mixture into a planting tray with a humidity dome on it with any vents just cracked. Once the surface is fully white and fuzzy I either use little chunks as innoculant under transplants or use about 1/3 of a tray in a 50 gallon batch of tea.
Total cost per tray has to run under 5$, might be much less
Nice Stephen I'll have to try that out. Seems like a fungal-dominant 'bomb' for sure. I don't think the delicate mycorrhizal fungal hyphae would survive, but the mycorrhizal spores have a hard exterior shell and would probably remain intact. I bet the white fuzzy part in your mixture is full of nutrient-cycling saprophytic fungi that are the primary decomposers of dead organic matter in soils, sounds good to me :)
mycorrhizae do not remain active unless they are attached to a living root system, they remain as spores, waiting for the right conditions to become activated.
Most plants will use a combination of endo and ecto mycrorrhiza in their quest for nutrition. It has been shown over the last two or three years that endo and ecto mycorrhiza have symbiotic relationships not only with the root systems that they grow in and around but also with each other.
Thus and endo mycorrhiza probably needs at least one of its symbiotic ecto mycorrhiza to interact with for it to be prime with relation to the hosts plants health and nutritional needs.
Both also interact with soil bacterium and the resulting enzymatic actions serve to feed the whole symbiotic interrelationship.