Availability of certain nutrients is constrained by limestone based soils in the Texas hill country. Chlorosis - iron deficiency-is well known. An application of mycorrhizae may benefit plant health, but how long does it last and what soil treatments are needed to sustain such a population?
Humus, granite sand, what else?
In south Florida, where I live, the soil are limestone based as well. I see chlorosis showing up in plants and trees growing in heavily disturbed soil, where the soil microflora have been severely or totally eliminated. Addition of mycorrhizae as well as enough organic matter to restore the natural equilibrium that was present before construction usually results in a correction of the chlorotic condition.
Mycorrhizae establish symbiotic relationships with plants, so the presence of these plants is necessary to sustain mycorrhizal populations. So long as the natural cycle is maintained, which includes regular or seasonal addition of organic matter to the soil, and the soil matrix remains undisturbed, the mycorrhizal population should continue once established.