Whats up with all these mushroom poisionings?

[harm_less]

Fungi are essential in soil biological function and its physical structure. I heard it claimed there are kilometres of hyphae in just a teaspoon of biologically healthy soil and these fungal strands serve as extensions to plant roots acting in a symbiotic relationship to allow plants to access far more water and nutrients than they are otherwise able to.

The mushrooms and toadstools we see are just the reproductive organs ('flowers') on a far larger organism. For this reason good observation of the environment from which you're harvesting mushrooms provides valuable information on what the fungi are living in symbiosis with in order to accurately identify them.

Yes a classic example of this is seeing red amnitas under pine trees, they have a symbiotic relationship, as you say to transport nutrients into their root systems.

Forested areas have a highly fungally dominant soil biome, as opposed to grassland or herbal soils in which bacteria dominate. The epitome of fungal dominance is in the boreal forests of the Northern hemisphere which are a crucial component of Earth's carbon cycle.

A demonstration of the reliance of forests on soil fungi is that the first planting of coniferous forests (on previously grazed land) is usually slow to progress whereas a previously forested area that is replanted grows faster as the soil has remaining fungi from the previous crop and so the symbiotic benefits are already established.