Issue link: https://read.dmtmag.com/i/787641
www.goodfruit.com GOOD FRUIT GROWER FEBRUARY 15, 2017 17 Spray the right way. Select days with low wind and spray at full rates. Wind scatters the product and reduces the rate, setting you up for resistance. Tank mix fungicides: Use products with different FRAC groups, or modes of action, in the same spray. Moyer advises mixing prod- ucts that are at high risk of resistance development with contact products, such as sulfur. "Sulfur's cheap, and it's easy to add into your spray rotation." Sulfur also doesn't prompt resis- tance. Never mix sulfur and oil. Some products come pre-mixed. R o t a t e f u n g i c i d e s : Again, rotate chemicals with different FRAC groups. Don't just switch trade names. Rotate within the season, not between seasons. That is, don't spray one chemical four times one year, then switch to another the next year. If you eliminate one mode of action, make sure you have others for replacement. Having too few options in your product toolbox will put resistance-development pressure on those remaining products. "The key is rota- tion. Don't overuse the same product repeatedly. We want to mix these things up." Don't panic. Resistance is not the end of the world. Yes, it has occurred in many grape growing areas, where they spray more often than in Washington. Washington growers have the benefit of learning from them. "But it is something we need to think about and not ignore," Moyer said. If these tips aren't enough, remember the R.U.L.E.S. of fungicide applications, taken straight from the Pacific Northwest Pest Management Handbooks: R = Rotate or mix fungicides of different groups. U = Use labeled rates and at times of critical disease control. L = Limit total number of applications of any fungicide group in a given growing season. E = Educate yourself about fungicide groups and resis- tance management tactics. S = Select fungicides that have multiple sites of activity. • Michelle Moyer GOOD FRUIT GROWER FILE Both the fruit and foliage show mildew symptoms, indicating that the fungicide product, timing or rate was not effective in controlling grape powdery mildew. Consider for your next planting: BRUCE PONDER • SUSAN WILKINSON • LOREN QUEEN • ADAM WEIL• DAVE WEIL 503-538-2131 • FAX: 503-538-7616 info@treeconnect.com www.treeconnect.com BENEFITS: • Disease tolerant • Cold hardy • Adapts well tvo all cherry-growing districts • Forms flower buds and comes into bearing quicker than Mazzard with a better distribution of flower buds 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 2017 ROOTS AVAILABLE NOW Call Tree Connection: 800-421-4001 CALL THE SIMPLOT LOCATION NEAREST YOU Moxee 509-248-5756 Prosser 509-973-2300 Quincy 509-787-1571 Royal City 509-346-2223 Sunnyside 509-837-6261 Helping tree fruit growers improve quality and profi tability through sound, science-based agronomic advice with the most innovative and cost-effective products available.