Issue link: http://read.dmtmag.com/i/64944
Cherries Symptoms on young trees are cankers that appear slightly sunken and darker than other areas. The inner canker tissue is orange to brown with brown streaks extending into healthy tissue above and below the canker. There may be a clear to amber ooze associated with the canker. Cankers can girdle limbs or trunks. Limbs or entire trees may die during hot weather. Pseudomonas population levels are high during bloom, low in summer, and high again during cooler fall temperatures and rain. Scientists have recently discovered a rootstock connection to bacterial canker OSU bulletin found at: extension .oregonstate.edu/bacterial_canker_of_s weet_cherry_in_oregon_may10-3.pdf . F susceptibility. STEPS to manage canker S cientists have developed the fol- lowing integrated approach to manage canker in cherries: 1. Avoid interplanting new with old trees. Rain can splash inoculum from old trees onto the young, healthy trees. 2. Do not use sprinkle irrigation on trees for the first three years. In late summer, reduce the amount of water applied for irrigation to harden off the tree so they are not as susceptible to winter injury. 3. Avoid all types of injuries to trees—mechanical, insect, or frost. Paint trunks with latex paint to prevent sunburn. 4. Delay pruning until spring, as late as May if possible. Avoid wet wounds. Less disease occurs in the summer. 5. Remove diseased branches and trees from the orchard and destroy them to reduce inoculum. 6. Plant resistant cultivars and root- stocks. Mazzard F12-1 is among the most resistant rootstocks; Rainier and Regina appear more resistant than Sweetheart and Bing. 7. Avoid planting in frost-prone and slow-drying areas. 8. Provide optimal soil conditions and balanced nutrition to get young trees off to a healthy start. 9. Control weeds, especially grasses, to reduce inoculum levels. 10. Pseudomonas has developed widespread resistance to copper. Use of copper fungicides may worsen the problem and should not be used. 11. Test for and control nematodes before planting a new orchard. High populations of ring nema- tode have been associated with more bacterial canker. 12. Avoid planting trees in wet condi- tions. Plant later in the spring when chances for dry weather are greater. 13. Minimize the length of orphan stubs. Cut stubs close to the lateral. A recent heading study showed that longer stubs left above the topmost lateral increased the chance of gummosis and dying tissue problems. www.goodfruit.com 364 365 366 367 368 369 370 Effects of Using Nutri-Cal with Nutri-K on Cherries % MARKETABLE GRADES OF BING CHERRIES 10 20 30 40 50 60 70 80 0 Nutri-Cal 36% Increase in Premium Grade 8.5-9! 56.7 44.2 20 PREMIUM MEDIUM 0 5 80 BRIX QUALITY OF BING CHERRIES 10 15 20 25 21.25% 17.00% or more information about bacterial canker in cherries read the OSU's Dr. Robert Spotts found significantly more dead Gisela 6 trees due to canker after one year in a rootstock trial comparing trees on Mazzard, Maxima, Colt, and Krymsk rootstocks. In the Netherlands, Johnson said that growers are experiencing a bac- terial canker problem similar to that in the Pacific Northwest in high-den- sity plum orchards. Within two years of planting, growers are losing plum trees to rapid decline from girdling cankers. Trees appeared healthy at planting. Researchers are experimenting with interstems to see if the problem is associated with rootstock and scion combinations. • Application Rate of 2 Quarts Nutri-Cal & 1 Quart Nutri-K Applied 6 times beginning at Petal Fall 2011 Application Dates: May 23, May 27, June 3, June 11, June 19, June 24 Ron Britt & Associates, Yakima, WA 2012 FIRMNESS EVALUATION OF BING CHERRIES 369.50 g % PREMIUM COLORS OF BING CHERRIES 100 95.75 366.28 g GRAMS FORCE TO SQUEEZE SKIN 1mm Make Sure You Always Ask For Make Sur ou A ay or ® ® C.S.I. CHEMICAL CORP. 800-247-2480www.nutri-cal.com Walt Grigg: 509-952-7558 10980 Hubbell Ave., Bondurant, Iowa 50035 PACIFIC NORTHWEST GOOD FRUIT GROWER MAY 15, 2012 31 75 80 85 90 95 89.25 COMBINED MAHOGANY & DARK MAHOGANY