HYBRID TREE CONE ORCHARD SYSTEM FOR APPLE
The hybrid tree cone (acronym HYTEC) orchard system was developed for the arid apple-producing districts of central Washington state. The goals of this training system include high early and sustained yield per hectare, high labor efficiency, and high fruit quality, including minimal fruit sunburn. Individual 3-m-tall, cone-shaped central leader trees have a basal width of 1.5 to 2.25 m. Tree density in single rows is 1400 to 2200 trees/ha, and each tree is supported with a pole or a post and wire support system. Appropriate dwarfing and precocious rootstocks for nonspur cultivars include M.9, Mark, and M.26. Annual pruning and/or bending the central leader encourages the development of strong lower scaffold branches, stimulates branching, and reduces tree height. The lower tier of horizontal scaffold limbs is permanent. Scaffold branches are shortened to fit within their allotted space by pruning to a weak lateral or spur. Upper limbs are trained horizontally and after bearing fruit are shortened to retain the tree's cone shape. Central leader height is limited to 3 m by pruning into older wood to a weak lateral.
Barritt, Bruce H. (1992). HYBRID TREE CONE ORCHARD SYSTEM FOR APPLE. Acta Hortic. 322, 87-92