Oregonism XL Endo/Ecto-MycorrhizaeRoots Organics Oregonism XL is a distinctive super soluble formulation of endo ectomycorrhizae, beneficial bacteria, and Trichoderma. The species of microorganisms in this product are specifically selected for fruiting and flowering plants with a tolerance to heavy fertilizing. Mycorrhizae colonize the root zone, forming a symbiosis with the plant's roots, massively increasing the size and effective surface area, facilitating greater nutrient uptake,