Issue link: http://read.dmtmag.com/i/245704
PHOTO COURTESY OF WEI QIAN G. Horticulture testing plot with more than 800 rootstock seedlings. "We are the first to evaluate blueberry rootstocks for commercial use," he said of the project. Though some people have tried grafting blueberry trees on a small scale in the past, Yang said this is the first major collaborative research effort to graft a blueberry tree that is viable for commercial growers. Grafting itself is not difficult, he said. "Right now, we are just trying to prove the concept," he said. "There are no commercial rootstocks for blueberries now." This is the first year researchers collected data on yield for the project in Oregon. Yang is still analyzing data on fruit quality factors such as firmness, size, and total acidity. He will investigate future yield projections and machine-harvesting potential next. In eastern Texas, where Yang first saw grafted blueberry trees, they grew as tall as 14 feet, had trunks four to five inches in diameter, and were planted at a spacThis is what a ing of eight by eight feet. For five-year-old commercial use, they would Duke blueberry be better planted into fruit"tree" looks ing walls kept to a height of like in Wei about eight feet with ten feet Qiang Yang's between rows, he thinks. experimental With blueberry bushes, planting. renewal pruning is used in which older canes are removed and new growth comes up from the ground. It is not clear how trees would need to be pruned. Top and side hedging would likely be tried, Yang said. As for rootstocks, he thinks they could be chosen for tolerance of high pH soils. Blueberries like acidic soils, optimum being about 4.8. Some varieties, such as Duke, have problems with root rots, and rootstocks could address disease resistance as well. Perfect climate Blueberry production has been increasing in the Pacific Northwest, where they are grown in arid conditions with irrigation. "The climate here is perfect," Yang said. The Oregon climate is moderate, so both northern highbush and southern rabbiteye varieties can be grown. Last year, Oregon produced about 72 million pounds on about 8,000 acres. Acreage has tripled since 2000. Michigan, the leading blueberry producer, generated 82 million pounds from lower-yielding plantations covering almost 20,000 acres. In both states, about half the berries are grown for fresh market and most of those are picked by hand. The other half, grown for processing, are picked by machine, but machine harvest is making inroads gradually for fresh market as well. Yang said that if results continue to show promise, blueberry trees could be ready for release to nurseries in about five years. Northwest FCS customer Kameron Jenks Northwest Farm Credit Services is a cooperative. When you become a customer you also become an owner. You have a voice and a vote in how our association does business. Plus, when we do well we share profits with you in the form of patronage. No bank does this. You borrow. You own. You earn. You grow. Learn more about the benefits of being a customer-owner at northwestfcs.com. • www.goodfruit.com GOOD FRUIT GROWER FEBRUARY 1, 2014 19