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Paul Rood has stuck with pears while others have pushed theirs out. He has a detailed management plan. That brown- looking grass in the alley has been suppressed with a low rate application of glyphosate. Pruning begins about November 1, after leaves have fallen but before the dead leaves on strikes are whipped away by winter winds. "The workers call them banderas—flags," he said, a description of those bunches of withered brown leaves that persist after normal leaf fall. Workers are instructed to take away all dead shoots—plus as least a foot of limb that is infected as well. Crews desucker all the trees in late June and early July, to get rid of that tender tis- sue that is so vulnerable to fireblight and also attracts pear psylla. His farm is within a few miles of Lake Michigan, and Rood believes his location protects him from the hail that often strikes orchards further inland. "Hail—any kind of leaf trauma—is terrible for causing fireblight in pears," he said. He sprays with streptomycin within a day of such an event and during rainy days during blossom time. "Pears have late blossoms," he said. "Even now, in July, there are some flowers in the orchard—enough to get infected." Tree nutrition and fireblight are also related. Nitrogen can contribute to shoot growth and fireblight sensitivity, and Rood applies nitrogen just once—about 2.5 pounds of urea per tree as a foliar spray after harvest but before leaf fall. Putting 25 pounds of urea in a hundred gallons of water delivers a pound of nitrogen to each tree, since he has about 100 trees per acre and applies 100 gallons per acre. The leaves absorb the nitrogen into shoots and spurs, where it contributes to vigor and good fruit set during bloom. "It's a compromise on fireblight. I want them to get a good start. Trees can look yellow and weak dur- ing bloom and a week after without that nitrogen spray. The late spray also kills scab spores, reducing inoculum in the orchard that will otherwise overwinter and erupt with spores the next spring," he said. He ground-applies potassium, also in the fall. "Pears respond well to potash," he said, "even if leaf analysis says no more is needed. It makes leaves bigger and darker green, without increasing fireblight." In the spring, he sprays once with boron, again believing it improves fruit set. One other practice he uses contributes a small amount of nitrogen during the growing season. After mowing the orchard once in the spring, he applies a low rate of glyphosate to stunt grass and reduce its competition for water and nutrients. At the same time, this chemical mowing encourages white Dutch clover, a low-growing ground cover that prevents erosion and fixes some nitrogen that becomes slowly available. Facing pear psylla Pear psylla is a problem very hard to approach with insecticides alone. Psylla fairly quickly becomes resistant to the insecticides. That was partly what drove pears from Michigan, he said. Rood recalls how, in the 1960s, a heavy freeze one year took out the pear crop. Growers cut back on sprays for psylla, encouraging a population build-up, and that same year, perthane, which was the one insecticide then effective against psylla, became unavailable. About that same time, the only pear canner in Michigan closed down. That combination of events was what brought out the bulldozers, he said. Today, Rood controls pear psylla with heavy use of oil—at least three gallons applied in two or three sprays early. Oil plus copper sulfate is the first one applied at dormant, followed by oil and lime sulfur at delayed dormant, then oil plus a pyrethroid such as Asana at white tip. "I quite firmly believe the key is to keep the psylla population low and not wait until they have a good start. That's the IPM (integrated pest management) recommendation in Washington State and California. Waiting for a threshold is not a good idea because the threshold for psylla is very low. Using this program, I can achieve quite good control." Rood believes the triple oil application targets overwintering psylla as adults, when they are vulnera- ble after a winter of fasting in the woods. "They can only feed on pear trees," he said of this sap-sucking insect. Psylla cause sap secretions that elicit secondary molds that discolor pears, and they also secrete toxins that reduce tree vitality. They become active with the first warm days of spring. The loss of pear acreage resulted in a loss of industry infrastructure that makes Rood's own pear venture more risky. Gerber is the only buyer of pears for processing. "I don't have a way to put stickers on fruit," he said, "so that keeps mine Rood built this platform especially for removing fireblight strikes. Controls let him steer, brake, clutch, shift gears, and control acceleration. Shears or saw on a long pole are powered by air. www.goodfruit.com out of the supermarket. I don't have any cold storage or any waxing equipment. I don't have washing equipment, and I can't sell pears with visible residue." Surround, the clay product western growers use for psylla control, leaves a heavy residue, so he doesn't use it. Another gap in pear industry infrastructure is a good dumping system. Most apple packers use water dumpers, he said. "Pears are heavier than water, so they don't float like apples." So, local apple packers don't usually pack pears. Given the problems with pear production, Rood isn't optimistic the East will make a comeback in pears. Fireblight-resistant varieties would help some, but people continue to love Bartletts. • GOOD FRUIT GROWER SEPTEMBER 2011 21 richard lehnert richard lehnert