Issue link: https://read.dmtmag.com/i/331109
www.goodfruit.com GOOD FRUIT GROWER JULY 2014 27 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 Roots available for SPRING DELIVERY 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 Leaf removal Another research project aims to change clus- ter morphology. Poni found that he could achieve a looser cluster by removing the first five to six primal or basal leaves before bloom. "If you try it in the vineyard, you've got to be careful," he said. "When you look at the vines, they look almost naked and you risk being chased around by the wine- maker," he said, jokingly. "But when you go back to the vineyard a couple of weeks later, it's hard to see if you really did remove any leaves." In a trial in a Sangiovese vineyard, early leaf removal reduced fruit set and decreased berry weight, Poni reported, but Brix, color, and percent of relative skin weight increased. Further studies that involved envel- oping the vines in bags for the season to measure gas exchange showed an increase in the net carbon exchange rate of the vines with leaves removed (3.31 micromoles per gram in the defoliated vines versus 2.43 in the control vines). He explained that removing leaves early allows the vine time to recover during the season. "The vine works harder to compensate for the missing leaves." He tested four different leaf removal machines and found the best results (least amount of injury to inflo- rescence or baby grapes) were from machines that use air pressure to blow leaves off the vine. Removing leaves late in the season can help slow down the ripening process. Preliminary work shows promising results from removing a few of the upper leaves late in the season at pre- or post-veraison. "We can delay ripening without negatively affecting other fruit qualities," Poni said. "In some very hot grow- ing areas, grapes in mid-August have high enough sugars to make wines at 14 percent alcohol, but the berries don't have the other good stuff, like color and phenols." • Removing the basal leaves of Trebbiano before bloom resulted in a looser cluster structure less susceptible to fungal diseases. Effects of early leaf removal on Sangiovese grapes Removing the basal leaves early resulted in smaller berries, better color, and higher Brix. Skin Relative Fruit Berry weight skin Color Treatment set (%) weight (g) (g/berry) weight (%) °Brix (mg/g) No leaf removal 32.5 3.0 0.195 6.5 18.3 0.787 Six basal leaves 29.5 2.4 0.194 8.0 20.1 1.133 removed prebloom SOURCE: Stefano Poni, et al.