Should one add more mycorrhizae to the soil?
Mycorrhizae have been found beneficial to many plants and are registered for use on some plants under certain soil conditions. These generally involve high value plants and soil conditions where mycorrhizal populations are low to non-existent. Examples of soils low in mycorrhizae may be sterilized potting soil, non-agricultural soil like subsoil in new housing developments or mine reclamation sites. Often the inoculants are most beneficial and useful for perennial plants, where they are inoculated once and remain for the life of the plant (trees, lawns). Under the Canadian Food Inspection Agency, soil organisms like mycorrhizae, must be tested to ensure they are safe (non-injurious to plants and the environment) and efficacious (they are beneficial and do what they are supposed to). Only after testing and regulatory approval are they eligible for use and sale in Canada.
