FLAT-CANOPIED OPEN CENTER TREES: A NEW DIRECTION FOR APPLE ORCHARD SYSTEMS

Flat-canopied open center (FCOC) trees on vigorous rootstocks in low planting densities are widely grown in Japan. These trees are well adapted to unfavorable land and climatic environments and well suited to very intensive culture for producing high quality apples. The fundamental principle of the framework structure of FCOC trees is that lateral branches, which bear fruiting branches, are free from the influence of the central leader or upright limbs, and also free from the direct effect of the root systems to a considerable extent. The advantages of the particular architectural structure of FCOC trees are: (1) canopy height can be efficiently reduced while still keeping a well-developed root system, (2) lateral branches can be grown from a large choice of shoots and they can be grown to fill up vacant canopy spaces and renewed when needed, thus ensuring a longer lifespan of the orchard, and (3) good light exposure can be maintained throughout the canopy. The growth of lateral branches can be characterized as “semi-independent”. New orchard systems can be developed by applying the architectural principles of FCOC framework and by using appropriate semi-dwarfing rootstocks.