Issue link: http://read.dmtmag.com/i/543863
48 AUGUST 2015 Good Fruit Grower www.goodfruit.com M echanical pruning is not just a labor-saving technique. In fact, the num- ber-one goal of mechan- ical pruning, or hedging, is to improve fruit quality in terms of size and eating quality, says Dr. Stefano Musacchi, research pomol- ogist with Washington State University in Wenatchee. "I think we already have a nice level of yield," he said. "If we expose fruit to the light they are sweeter compared to fruit devel- oped in the shade. I'm thinking we have to look not only to maximize yield but to maximize quality because quality is the key issue." Musacchi and colleague Karen Lewis, WSU extension specialist, have been conducting trials in commercial orchards to study the effects of hedging, test var- ious timings, and look at the impact of fruit sunburn. They have trials in a Kanzi apple orchard owned by Columbia Fruit Packers and in Pink Lady and Fuji orchards owned by McDougall and Sons. They also have a trial with Cosmic Crisp (WA 38) at WSU's Prosser research orchard. In addition, Musacchi is evaluating mechanical pruning of Bartlett pears at a McDougall orchard at Monitor in the Wenatchee Valley. Not new Musacchi said mechanical pruning is not new. It was tried in Europe in the 1970s but didn't catch on because apple trees were not grown on dwarfing root- stocks at that time and the pruning was done in winter, so the trees responded with vigorous growth. "You will have a very strong reaction, and this will make your tree very angry with you and make it grow in a strong way," he said. Since then, French horticulturists have developed the concept of the fruiting wall, with closely spaced trees planted on dwarfing rootstocks. The trees are calmer and more balanced, with a struc- ture made up primarily of small fruiting branches, and are easy to summer prune mechanically without fear of stimulating too much vigor. When shoots and leaves are removed HELP with hedging When can it be done and will it increase fruit sunburn? by Geraldine Warner Consider for your next planting: • BRUCE PONDER • SUSAN WILKINSON • ADAM WEIL • DAVE WEIL 503-538-2131 • FAX: 503-538-7616 info@treeconnect.com www.treeconnect.com BENEFITS: • Disease tolerant • Cold hardy • Adapts well to all cherry-growing districts • Forms flower buds and comes into bearing quicker than Mazzard with a better distribution of flower buds Now booking orders for 2016 Call Tree Connection: 800-421-4001 Dwarfing Cherry Rootstock Krymsk ® 5 Krymsk ® 6 [cv. VSL-2, USPP 15,723] [cv. LC-52, USPP 16,114] "Krymsk ® 5 and Krymsk ® 6 cherry rootstocks have proven to be the best rootstock for our orchards. They are yield efficient, grow and adapt well, and are cold hardy." —John Morton The Dalles, Oregon