MANAGING AVAILABLE WATER IN THE ROOT ZONE FOR INCREASED PRODUCTIVITY - ARE WE PLAYING OUR PART?
All too often, it seems to me, we become concerned with the precision with which we measure one parameter of response to variation in an edaphic growth factor, and ignore other responses. In fact, how often do we measure a response like yield per tree - and then assume that this is synonymous with the response that really matters, productivity. If we work with a single tree it is clear that the larger this unit becomes the greater will be its (ultimate) yield potential - but high density planting on dwarf stocks has been well established as a means of increasing yield per unit area.
With this latter view in mind, we make pleas to the plant breeders and selectors to produce dwarfing stocks and spur-type varieties - to provide trees that are more readily managed by the gross management techniques we devise.
But there is nothing absolute about the size of tree a given rootstock will produce. Edaphic factors can exercise just as great an influence on tree as the rootstocks - accidentally or otherwise.