Issue link: http://read.dmtmag.com/i/31248
LIKE OUR ROOTSTOCK, our service will grow on you. ALL FRUIT TREE ROOTSTOCK IS OREGON CERTIFIED VIRUS FREE. tolerance during flower bud initiation. When sweet cherries “He needs me because don’t get enough hours of temperatures below 40˚F, they don’t grow or flower normally. “Leaves don’t emerge right, and trees come into bloom sporadi- cally,” Andersen said. Varieties like Bing require 700 chill hours, and the southern San Joaquin Valley struggles some years to get 250. Chill hours requirement is a trait that breeders can select for. Andersen looks for signs of abnormal growth and flowering, and culls those seedlings that show no promise. But because of the interest in good early varieties in high chill areas, they are not automati- cally discarded. Some of them go to growers in higher chill areas for trials to compare them to varieties like Chelan. Heat tolerance Heat tolerance is a different trait. Trees that can’t toler- ate heat during the critical time of flower formation, right after harvest in the hot San Joaquin Valley climate of early June, produce a high amount of cherries the next year that are either complete doubles or partial doubles, called beaks. Some also have sutures, a dimple from which a crack can develop. Brooks has been the primary variety grown in Califor- nia south of Fresno, Andersen said, but it’s a “dirty vari- ety,” he said, meaning that it requires sorting to remove beaks and doubles. Developed by the University of Cali- cherries ripen at the same time as grapes are blooming.” —Bob Andersen fornia, Brooks is a large and firm cherry that ripens ahead of Bing. It is suscep- tible to cracking in rain. Bing can’t be grown there at all, he said. In selecting, Andersen collects fruit from the south side of seedling trees, the hottest side, and technicians count the number of doubled or beaked fruit, looking for those lots having a low percentage of defective cherries. All the other quality factors that sweet cherries need must be there in combination with good heat tolerance and/or low chill characteristics in the seedlings selected as potential varieties for International Fruit Genetics, Andersen said. Bitterness and small fruit are common traits, especially in some of the wild seedling material Cain used in the making the crosses. To evaluate these traits, taste buds still work, and Andersen has a wealth of experience looking for tasty cherries. The cherries Andersen finds suitable for further devel- opment go to others in the proper climatic areas for field trials and evaluation. When he’s not in California, Andersen does consulting work with some stone fruit growers on the East Coast, especially those trying high tunnel production. And he also works closely with Wally Heuser and Laura Heuser Gale at International Plant Management in Lawrence, Michigan. They have a contract to commercialize vari- eties Andersen had bred and was evaluating when he was at Cornell (see “Cherry breeding is slow work”). • canby, oregon 503-263-6405 Toll Free 1-800-852-2018 see all of our offerings, plus availabilities, at www.willamettenurseries.com NEW 36 MAY 15, 2011 GOOD FRUIT GROWER www.goodfruit.com