The great majority of the sites for agroforestry practice have actual or potentially low soil fertility.
In many cases low soil fertility is inherent, and in others it is the result of intensive cropping of fragile tropical soils or the result of erosion of topsoil.
These are situations where management of mycorrhizal systems are likely to be of great benefit, for the main mode of mycorrhizal stimulus of plant growth is via increased nutrient uptake.
However, the mycorrhizal system can also be perceived as an alternate root 'strategy' (Bowen, 1980) and mycorrhizal
benefits may well come also in combating effects of common soil limitations to growth, such as
soil salinity or soil acidity.