There are several “keystone” or critical soil organisms that are important to human’s survival. Arbuscular mycorrhizal (AM) fungi are a type of fungi that infect plant roots root to recycle soil nutrients that increase crop growth, vigor, and yield. About 250 AM fungi species infect 80-90% of all agricultural annual crops. This beneficial (symbiotic) association started over 450 million years ago, when newly evolving plants had few roots and relied on AM fungi to gather soil nutrients like phosphorus (P), sulfur, nitrogen, and many micronutrients. AM fungi form a mycorrhizal network with plant roots, extending out 6-18 inches from a root hair, increasing surface area for soil nutrient extraction by 20X. AM fungi hyphae are 1/10 the size of a root hair, so tiny AM hyphae extract soil nutrients unavailable to plant roots. "There are 1 to 20 meters of AM hyphae in each gram (finger nail size) of soil or maybe 5 miles of AM fungi hyphae in a pound of soil" (Sylvia et al 2005). Th...