Wow that is fascinating John ! So the spores that are released with water go up, form clouds, rain back down and then what? Seems like they are "seeding" themselves , potentially over thousands of miles, and bringing their own irrigation with them ?
Have you found any other research where someone has examined rain or even the clouds themselves for % of spore content?
I have some really deep dark aspen forest at my place. I try to leave it undisturbed except for a very occasional hike through on deer trails. It is usually full of mushrooms and is very humid under the canopy. Do you think that the spores are escaping from under the canopy or just creating a "micro rain" within the system?
Good input about your own land. I think it's interesting how Sepp Holzer has taken his approach ( and Geoff Lawton too, I think) and gone to places where it doesn't rain and where there are no streams. After working some broad based permaculture for a few years, they have observed clouds forming regularly over the hills. Rain starts to fall and eventually they have streams. In some very dry places, like the Atacama Desert in Chile, life grows just from dew. I imagine that morning dew can combine with spores and pollen. I think so many of the parts work together. If the mycorrhizal fungi can help the tree survive, it can make mushrooms, more other life will live, and it all works together.