Issue link: http://read.dmtmag.com/i/657340
34 APRIL 1, 2016 Good Fruit Grower www.goodfruit.com expensive, tree fruit growers have looked for ways to mechanize that not only reduce the need for workers but also make tasks simpler with fewer rules and decisions. A hedger makes a systematic approach simpler, using blades to shape an orchard canopy into a narrow "box," moving from three-dimensional trees to a two-dimen- sional wall, Mario Miranda Sazo, a Cornell University extension specialist in Newark, New York, said during his conference presentation. Sazo began trials in 2011, hedging tall spindle trees back to 18 to 20 inches during dormancy and 22 to 26 inches in the summer. The canopy ended up about as wide as the herbicide strip around the trunks. Rod Farrow, a New York grower and one of Sazo's collaborators, instructed conference attendees who are planting to keep their canopies narrow to maximize sun exposure and make way for mechanized tools such as hedgers as their trees age. Don't go beyond 3 feet, he warned. "Anything you plant, if you're thinking beyond 3 feet, it's obsolete, in my opinion," said Farrow, an association board member generally regarded as an early adopter of technology and high effi ciency systems. At Michigan State University, Phil Schwallier, district horticulture educator, began hedging trials in 2014 and spent the fi rst two years demonstrating and practicing on a block of seven different varieties, most of the trees on Nic 29 rootstock, at different times of the year at the Clarksville Research Center. The tall spindle trees are 10 years old and had never been hedged. "That's all we have to work with," he said in an inter- view after the conference. Hedging is easiest when trees are trained from plant- ing to accommodate hedgers, but the mature block will give him and his colleagues information about how to transition from hand pruning to hedging. He will begin quantifying results this year and expects to see the best increase in good return bloom from bloom-time hedging and June hedging, some return bloom from a July hedging and no impact from August or postharvest hedging, he said. Hedging trials W ashington State University researchers are in the third and fi nal year of mechanical hedging trials in apple, pear and cherry orchards to compare timings and techniques, as well as demonstrate the machinery for growers. Here are some of the details of the experiments and results so far. ◆ Karen Lewis, a Washington State University regional extension specialist, conducted the apple trials. Fuji apples on a Nic 29 roostock planted in 2009 and trained to slender spindle. The Masilin strain of Cripps Pink apple trials were on Malling 9.337 rootstock on spindle trees planted in 2012. All apple blocks were already established. Among the results after two years: —In Fujis, hedging was 40 percent to 70 percent faster than hand pruning. Hedging also reduced shoot growth without reducing return bloom or fruit quality. —In both varieties, hedging pushed fruit and vegetative buds in blind wood near the trunk. —In both varieties, Lewis found no negative impacts on fruit quality from mechanical pruning compared to pruning by hand or a combination of the two. ◆ Dr. Stefano Musacchi conducted the pear trials in Bartlett pears on OHF87 rootstocks trained to spindle and planted in 2012 in Monitor, Washington. The block was set up specifi cally for hedging. Among the results after only one year: —A combination of mechanical hedging and hand pruning produced a greater proportion of large fruit, more than 70 millimeters in diameter, than hand pruning alone, and a smaller proportion of small fruit less than 55 millimeters in diameter. ◆ Dr. Matt Whiting led the cherry trials, which featured Tieton cherries on Gisela 5 rootstocks trained to UFO and planted in 2008 and already established. Among the results after two years: —Mechanical hedging was 29 times faster than hand pruning alone and 17 times faster than a combination of the two. —R. Courtney "The days of farming apple trees with permanent wood are over. That's over. It's obsolete." —Leonard Ligon