Issue link: https://read.dmtmag.com/i/215151
Wind machines in the background have become a common feature on Fruit Ridge, many of them added after the big freeze of 2012. —Limb renewal. All scaffolds are removed as they become too large for the available space and become out of balance within the tree. —Early fruiting. Fruiting in the second and third leaf is essential to keep a low tree vigor level and provide income from early fruit sales. In tests, this system achieved cumulative production of more than 3,000 bushels in the first five years, resulting in a 40 percent higher crop value than the slender vertical axis and Sol Axis planting systems. PHOTOS BY RICHARD LEHNERT Future vision The basic elements of tall spindle are these, as described in a paper by Robinson, Hoying, and Fargione: —High density. The optimum tall spindle spacing for an average vigor variety and soil is 3 feet by 11 feet, or 1,289 trees per acre. —Full dwarfing rootstocks. The most successful tall spindle orchards established to date have been on M.9 and B.9. Precocious dwarfing stocks are important since early cropping is essential. Cornell is also developing a series of rootstocks resistant to fireblight and replant disease. —Highly feathered nursery trees. Nursery stock ideally have from 10 to 15 feathers per tree. —Minimal pruning at planting. No heading. —Support system. To carry the crop and support potentially brittle rootstocks. —Branch devigoration. Upright scaffold branches are devigorated by bending them below the horizontal. This early investment of labor pays off in early cropping and less pruning later. www.goodfruit.com In addition to high, early yields, a key goal is to increase the percentage of high quality fruit, Robinson said. That means having narrow canopies that allow good exposure to light from bottom to top. This has led Robinson to examine the work of Alberto Dorigoni in Italy, who is narrowing canopies with mechanical hedging to form tree walls, and Robinson's work last year focused on finding the best timing for hedging. The next economic challenge is labor reduction. "We need to grow apples with half the labor we now use," he said. That gives him a target of 180 hours per acre, compared with about 360 now. Key ingredients are machines—platforms to thin, prune, and serve as carriers for harvest crews, but also hedgers to do much of the pruning now done by hand. Chemicals play a role as well. Chemical thinning can cut thinning labor by half, and Robinson has been working with colleague Dr. Alan Lakso to develop a carbohydrate model to make chemical thinning more effective. The model predicts the sensitivity of fruitlets to drop, set, and thinning, based on the carbohydrate balance in the tree. • GOOD FRUIT GROWER DECEMBER 2013 19