Issue link: https://read.dmtmag.com/i/506700
40 MAY 15, 2015 GOOD FRUIT GROWER www.goodfruit.com SUPER SLENDER AXE A lso called the super spindle axe, the super slender axe was developed as a modification of the spindle to gain greater control of tree growth. The system requires a trellis to support the trees, which have a small trunk diameter and are planted 20 to 40 inches apart in rows 10 to 11.5 feet apart. The super slender axe system needs dwarfing and precocious rootstocks such as Gisela 5 and Gisela 3. In the case of low vigor sites or self-fertile varieties, it may be possible to use more vigorous, precocious rootstocks, such as Gisela 6 or Gisela 12. Varieties with good vigor, upright growth habits, and the ability to produce lateral shoots are preferred. The most important variety characteristic is the capacity to produce fruit on basal buds of one-year-old shoots. The production habit of this system is significantly different from other systems. Instead of producing fruit on spurs with multiple small flower buds, it utilizes the solitary large flower buds at the base of one-year-old shoots. This results in a favorable fruit-to-leaf ratio that yields good fruit size and quality. The low production capacity per tree is compensated for by the high planting density. KYM GREEN BUSH T he Kym Green Bush (KGB) is the only system of the eight that creates a fully pedestrian orchard—one that can be harvested without ladders or platforms. Tree formation is easy and requires minimal labor; mature pruning is simple and follows a repeatable plan. Although most vari- eties grow and produce well with a KGB system, it is not recommended for non-spur type varieties such as Regina and Attika, which produce a signif- icant proportion of fruit at the base of 1-year-old shoots. This wood is eliminated in the KGB system. The SEVEN systems guide by incorporating many new train- ing system concepts and strategies from around the world that are innovative, productive, and labor efficient," Lang told Good Fruit Grower. "In my international travels, growers everywhere have asked for a step-by-step guide that can help them understand the rationale behind different canopy train- ing systems and how to match them to rootstocks of varying vigor and precocity as well as local growing conditions. "We have really been quite fortunate to compile such a guide that directly draws upon not only the international expertise of scientists such as Matthew Whiting, Stefano Musacchi, Lynn Long, and myself, but also on our many collab- orative experiences with progressive and creative cherry growers, consultants, and nurserymen around the world." Long said he wrote the first cherry training system manual in 2002. "But it has become obvious in recent years that there was a critical need for a new manual that expanded the number of systems featured. Scientists such as Drs. Greg Lang, Matt Whiting and Stefano Musacchi have developed some outstanding science-based systems in the last few years that increase precocity, allowing for high yields of premium quality fruit while easing labor needs. "These new systems are being planted all over the world, yet, until this guide came out, there was no definite source of information where growers could obtain accurate instructions on how to properly train these trees." The natural tree Undisturbed in its native environment, the young sweet cherry will grow as a central leader tree, the authors explain in the guide's introduction. Growth is rapid and apical dominance is strong. Thus, the tree tends to branch only just below the terminal bud of annual growth, can grow SPANISH BUSH T he establishment years of the KGB system are similar to the Spanish bush. But once the structure is formed, the two systems diverge. In a Spanish bush tree, all upright leaders are permanent and fruit is produced on small laterals that are renewed regularly. In a KGB tree, all vertical leaders eventually are renewed and the only permanent wood is the lower framework of the tree. The KGB uses vigorous or semi-vigorous rootstocks. Growers can choose the number of vertical leaders to moderate the tree vigor. Both Spanish bush and KGB are freestanding and require no trellis. They need spacing of 6 to 8 feet between trees and 14 to 18 feet between rows. STEEP LEADER T he steep leader training system was developed by growers in Washington State. Three or four vertical leaders emerge from the base of the tree and horizontal scaffold branches develop from them. Fruiting occurs on temporary lateral branches that grow from the vertical leaders and horizontal scaffolds. Each leader mimics a one-sided spindle tree. The trees are quite vigorous—so spacing needs to be 10 to 16 feet between trees, depending on the rootstock, and 14 to 18 feet between rows. TALL SPINDLE AXE T he tall spindle axe tree canopy takes advantage of the sweet cherry tree's natural tendency to develop a central leader. However, this system modifies the natural branching habit, replacing annual tiers of four to five strong lateral branches with a continuously spiraled whorl of moderately vigorous lateral branches, preferably forming about 10 or more per year during canopy development, to ultimately form a conical "Christmas tree" shape. The system is further differentiated by two key concepts: —Annual heading of lateral shoots to balance leaf-to-fruit ratios and future crop loads; —Annual renewal of the oldest fruiting branches so that the only per- manent structure is the central leader. The tall spindle axe is a training system well-suited for dwarfing to semi-vigorous rootstocks, or vigorous rootstocks on weak soils, since growth is comprised primarily of lateral shoots of moderate vigor borne on a single vertical leader. Spacing is 5 to 8 feet between trees and 11 to 14 feet between rows. ILLUSTRATIONS FROM CHERRY TRAINING SYSTEMS