Issue link: https://read.dmtmag.com/i/50987
Michigan State University entomology Matt Grieshop heads a project involving 28 researchers nationwide. application timing, reduce drift, and improve deposition in a high- density orchard at Fowler Farms in New York State. Preliminary results were promising. Their paper identified how such a system might be laid out and addressed the main engineering challenges of pipe diameter, sizes, emit- ters, flow rates, pressure changes, and injection systems. Inexpensive emitters were fitted to small-bore irrigation pipes mounted on the top and middle trellis wires. Better timing The Solid-Set Canopy Delivery system could have Entomologist Larry Gut has been experimenting with the Solid-Set Canopy Delivery system to apply codling moth mating disruption pheromone in an orchard at Trevor Nichols Research Center in Fennville, Michigan. several advantages, according to Grieshop. Instead of taking hours of up-and-down-each-row tractor driving, with its costs in time, fuel, and equipment, turning on the fixed system could pump critical pesticides to fight insects and diseases through plastic lines to micro- emitters in every tree in minutes. No more carving up the alleys in wet, sloppy condi- tions. No more spraying long hours into the night to take advantage of precious time and low-wind conditions. Timing has other important aspects as well. Dr. Larry Gut, an entomologist at MSU and a partici- pant in the project, and Grieshop have studied the behav- ior of codling moth and found it flies four hours a night at "Orchard spray technology has not kept up with the changes that have taken place in the horticultural side of tree fruit most, starting just before sunset, but it doesn't fly if the temperature is below 60 degrees or if it's even moderately windy. A fixed-in-place, all-at-one-time system could target spraying of codling moth only when it is active. Gut is working on the idea of applying expensive mating disruption pheromones only during those brief times when they are needed. "Timing is also important with the use of reduced-risk insecticides," Grieshop said. "They are quite target specific and often have a short residual period." Grieshop heads the organic pest management program at MSU, so he is also concerned about organic program chemicals that are often easily washed off, have short residual activity, or depend on thorough coverage for their effectiveness. This system addresses all these issues. Targeted delivery A sociologist is evaluating such issues as worker safety and the urban/agricultural interface, where people, noise, and spray drift are all growing concerns. While enclosed tractor cabs and space-suit-like personal protection equipment are parts of modern spray application, exposure is still more likely than it would be if a worker was mixing chemicals and turning on equipment in a centralized spray facility away from the orchard. If workers are not in the orchard during spray application, it also opens the possibility of using mate- rials, like Guthion (azinphos-methyl), that are hazardous to workers but might be environmentally less damaging than reduced-risk materials. One of Grieshop's interests in the project is the impact such a system might have on orchard ecology. What might happen to soil compaction and vegetation management if tractors hauling sprayers were removed from the orchard? What might the impact be on natural enemies and pollinators? Could less mechanical damage to trees reduce fireblight or cankers? While it might be more expensive initially to install a permanent, fixed-in-place spray application system, the costs of operation should be much less if the costs of equipment, fuel, and labor for sprayer, tractor, and sprayer operator are eliminated. Grieshop requested funding for five years, but received two years of funding. He is hoping that if research funds continue to be available and the project shows merit, it might be refunded. • www.goodfruit.com GOOD FRUIT GROWER DECEMBER 2011 25 production." —Matt Grieshop richard lehnert richard lehnert