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www.goodfruit.com Good Fruit Grower FEBRUARY 1, 2015 19 Figure 7 Careful tree training during the first growing season is pivotal. These Rival apricot trees were of poor quality when planted, but still managed to grow four leaders each, which reached the top wires of an Open Tatura eight months later. spacing and density), the much taller vertical Fruiting Wall needs ladders or platforms. When fruit trees are managed from the ground, it is easier for the orchardist, labor is more efficient, the labor force can be expanded to include male and female work- ers of different ages, and it is easier to manage unskilled labor. The small trees have less internal shading than large trees do. Regulations and penalties for occupational health and safety may eventually force orchardists to work from the ground. Platforms and other mechanical aids have less value in small orchards that risk being overcapi- talized and in countries with plenty of cheap labor. On the Open Tatura system, some stone fruit plantings trained with four leaders produce a crop in the second year, and most types of fruit trees reach their plateau yield within six years. Swiss researchers have recently shown that V-shaped canopies have higher yields and fruit of better quality than vertical cano- pies do. However, it is more expensive to establish an orchard with V-shaped trees than an orchard with vertically trained trees. Open Tatura usually has rows that are 4.5 meters (15 feet) wide, giving more space for equipment and bins to pass between rows than there is in the popular vertical Fruiting Wall with only 3.5 meters (11.5 feet) between rows. Fruit on the Open Tatura is generally little damaged by wind. In parts of New Zealand and the United States, angled canopies are preferred where strong winds are a problem. In 2012, an Open Tatura orchard in north Queensland, Australia, withstood cyclonic winds of 280 kilometers (175 miles) per hour, while freestanding trees and trees on T-trellis were ripped out of the ground. Angled canopies are successful, because the wind skims over the rough elements of the high-density trees. For an Open Tatura with four-leader trees, a planting density of 2,222 trees per hectare (900 per acre) is affordable. With four leaders per tree and two leaders on each side of the trunk, there are 500 millimetres (20 inches) between leaders. On the other hand, the canopy develops more slowly with fewer trees per hectare and six leaders per tree, because it takes more time, care, and leader-bending than with four leaders. There is one pitfall in the early develop- ment of the four-leader system. The inner two shoots tend to be more vigorous than the outer two shoots (see Figure 1). The orchardist needs to subdue (cut back to a short stub) the two inner shoots to give the two outer shoots a good head start. At the end of the first growing season, the two inner shoots usually catch up with the growth of the two outer shoots (see Figures 2 and 3). Some countries and regions specialize in apples because different types of spindle trees on low-vigor root- stocks appear to produce profitable apples. However, in countries like Australia, many orchardists grow different cultivars of both stone and pome fruit, and use various systems for training trees. Some systems continue to evolve to suit different fruit species and conditions. The branchless multileader tree, for example, can be used for both angled and vertical trees and can maintain optimum and affordable tree density. Trees are managed simply and vigor controlled without size-controlling rootstocks, yet yield and packouts of fruit of high quality are increased. • Bas Van den Ende is a tree fruit consultant in Australia's Goulburn Valley. Introducing Madex HP for control of codling moth and oriental fruit moth larvae. Now you have a selection of highly e ective granuloviruses. So potent they can be used at ultra-low rates for cost-e ective control. Ideal for managing insecticide resistance and residues. Four-hour reentry interval (REI) and zero plant harvest interval (PHI). OMRI ® Listed andNOPApproved. Double Trouble for Codling and Oriental Fruit Moths. CYD-X ® HP and ma - dex ® hp The most potent codling moth and oriental fruit moth viruses...ever. © 2015 Certis USA ] [ © 2015 Certis USA 1-800-250-5024 • www.CertisUSA.com