Issue link: https://read.dmtmag.com/i/506700
www.goodfruit.com GOOD FRUIT GROWER MAY 15, 2015 39 system from work that began when he was a graduate student mentored by Greg Lang at Washington State University; —Greg Lang, now a professor of hor- ticulture at Michigan State University, a leader in explaining cherry tree physiol- ogy, the tree's response to pruning and training, and a key figure in the NC-140 project, which since 2010 has investigated the performance of four of the training systems in cherry growing regions across the United States and Canada. "This guide has essentially been 10 years in the making, greatly expanding upon Lynn Long's excellent previous Study shows value of high-density cherry systems S tefano Musacchi, who was hired in 2013 to fill Washington State University's endowed chair in tree fruit physiology and management, has been one of the world's active participants in designing and evaluating sweet cherry production systems. In 2007, he and colleagues Federico Gagliardi and Sara Serra at the University of Bologna in Italy began what would become a seven-year period of observation and data collection on three high-density training systems. The result of their work was reported in a paper published in HortScience in March this year. The study evaluated performance of ten sweet cherry varieties on Gisela 5 and Gisela 6 rootstocks in the three training systems: spindle, V-system, or super spindle axe (SSA). Only some of the varieties studied are grown in the United States, but, in general, the study produced useful conclusions. "Our results demonstrated that it is possible to develop a high-den- sity-planted sweet cherry orchard producing a significant yield by the second and third year after planting," they say. "The SSA and V-systems, in combination with the correct cultivar, guaranteed a high level of production and positively affected fruit quality." The V-system and SSA produced higher yields than spindle on both rootstocks, on all the varieties tested. Generally speaking, low production per tree (7 to 12 pounds) was compen- sated for by a high number of trees, they reported, and the quality was very high. More than 90 percent of the fruit had a diameter more than 28 mm (9-1/2 row). "Pruning will be a key factor to minimize wood aging and yield reduction," they say. The high-density training systems, particularly the SSA in combination with short-pruning, offers the possibility for orchard mechanization. "For mechanical pruning, the small width of the trees could allow lopping machines to shorten all the one-year-old shoots at four to five buds of length." Among the three systems grafted on Gisela 5, trees trained to the spindle system had the highest trunk cross-sectional area, followed by V-system and SSA. Choice of cultivar was important for yield, sweetness, and cherry size. Different cultivars also respond differently to the different pruning methods, depending on where they bear most of their cherries—on basal buds or spurs. —R. Lehnert COURTESY STEFANO MUSACCHI 6ZHHWFKHUULHVDUHERUQHRQ½RZHUV DWWKHEDVHRIVKRUWOLPEVLQWKHVXSHU VSLQGOHD[HV\VWHP "These new systems are being planted all over the world, yet, until this guide came out, ϔ where growers could obtain accurate instructions on how to properly train these trees." —Lynn Long