by producing glues, hyphae strands

by producing glues, hyphae strands and tunnels for air and water.
Good microbes also eat a lot of toxic material that would otherwise make for poisonous soil,
but they do need healthy organic soil to consume with it.
An imbalance of soil microbes can result in parasitic infestations, root disease, breakdown of the soil structure and build-up of toxic compounds. When the soils are repeatedly treated with toxic chemicals, the balance between good and bad is disrupted and the soils can actually become toxic to plants.