Issue link: http://read.dmtmag.com/i/459886
32 FEBRUARY 15, 2015 GOOD FRUIT GROWER www.goodfruit.com Small populations don't trigger a pathogenic outbreak but large ones do. Bacteria multiply at a rate that's governed by tempera- ture and resources, Smith explained. The more moisture and food the bacteria have available, the faster they can grow at a given temperature. Blight bacteria can grow in a temperature range of 50°F to 90°F, and do best from 78°F to 90°F. Growth rate slows above 90°F and stops at around 100°F. Past models relied on mean temperatures (aver- age between the high and low for the day), but Smith says they were too crude. Dr. Larry Pusey, retired U.S. Department of Agriculture researcher, found that peak temperatures were more important than mean tem- peratures relative to rate of blight bacteria growth. "It turns out that just one day at 88°F is enough to build up a colony," said Smith. 5. You must identify your orchard fire blight risk. To use the model, you must first determine fire blight pressure (high, medium, or low) for your orchard. "It's very important to know how much fire blight is in your vicinity because it makes a huge difference in the tem- peratures needed to trigger infection," he said. Smith suggested that a guideline of 400 feet adjacent to the orchard be used in determining fire blight in the neigh- borhood. If you had no fire blight in your orchard and neighborhood last year, risk this year will be low. But a missed canker that wasn't cut out in the winter can result in an orchard 'hot spot' and set the orchard up for a worst-case scenario. 6. The model's risk value thresholds are to be used as a guideline. Threshold numbers are not absolute, but should be used as guidelines. Generally, the risk numbers work out well, he said, noting that a high risk number of 299 should not be considered much lower in risk than 301. "It turns out that just one day at 88°F is enough to build up a colony." —Tim Smith $QRUFKDUGVXIIHULQJIURP¼UHEOLJKW7KHGLVHDVHLVWULJJHUHGE\PRLVWXUH Introduces the NEW FRUIT HARVESTER LABOR SAVING Exceptional Gentle Handling Exceptional Gentle Handling Reduces Picking Time Reduces Picking Time Gentle Bin Delivery Gentle Bin Delivery Rotating Bin Filler Rotating Bin Filler Small, Compact, Stable And Quiet Small, Compact, Stable And Quiet This new REVO apple harvesting system ensures quality fruit all the way to the bin. The conveyor belts placed on the extremities of the harvester convey fruit to the main belt, then seamlessly conveys fruit to the bin with one single belt exchange. This self-propelled 4WD Fruit Harvester reduces picking time, labor costs and guarantees excellent results by moving fruit faster, more gently and more effi ciently. As the bin rotates the fruit is lowered gently into the bin as it fi lls. Picking Ease From Platform Or Ground Picking Ease From Platform Or Ground See Your Nearest Blueline Equipment Dealer Today. . . See Your Nearest Blueline Equipment Dealer Today. . . CALIFORNIA 509-840-1828 WALLA WALLA 509-525-4550 PASCO 509-544-6678 UNION GAP 509-248-8411 SUNNYSIDE 509-839-2066 GEORGE 509-785-2595 CLE ELUM 509-674-4544 MATTAWA 509-932-4001