Good Fruit Grower

January 15

Issue link:

Contents of this Issue


Page 32 of 47

or more information, see the article "Frost protection strategies" by Richard Lehnert in the February 1, 2013, issue of Good Fruit Grower. Searchable archives can be found at the Web site F work for them," Battany said. Using 35-foot towers that track air temperatures at five-foot intervals above the vineyard floor, researchers have been seeking to understand the conditions under which wind machines will be most effective. The machines work by drawing down warmer air, dispersing the cold air surrounding the vines. Research has found that they're most effective when there's at least a two-degree difference between the air temperatures at 35 feet above the vineyard floor and 5 feet. "The presence of that temperature inversion is going to be a key factor in permitting a wind machine to provide a good degree of protection," Battany said. "Otherwise, a wind machine may not be a good investment for that area." Growers with sites where wind machines tend not to be effective, and where water is in short supply, might need to consider adjusting trellising or replanting the vineyard to varieties more suitable for local conditions. "We [might] need to rethink some of the varieties that we're trying to make ripen in certain areas," Battany said. "If we have to train vines very low to the ground in order to get them to ripen, that might tell us that variety isn't the most suitable for that climate." Many growers in southern British Columbia faced just that kind of choice when a hard frost hit in early October 2008. Many vines still had fruit on them and hadn't yet entered senescence. An arctic front in late December then dumped snow and extreme low temperatures on the vineyards; temperatures in one of Constellation Brands's blocks near Oliver recorded a temperature of -26.8 degrees Celsius (-16.2 degrees Fahrenheit). Air drainage Ironically, it was in vineyards further north, where temperatures were warmer but site conditions allowed cold air to pool, that damage was the worst. "Air drainage is everything," Frank Hellwig, then national director of vineyard operations for Constellation, told growers attending the grape council conference the following summer. "It can be -26°C, but if you're on a slope where the air's continually flowing as water does down a slope, then it seems to make a hell of a difference. If that air sits, then that's where you get the worst damage." Hellwig said a level site with good air drainage, as well as appropriate vine management, can significantly reduce the risk of damage regardless of variety. But for Battany, if trellising for specific varieties increases risks, then growers need to think twice. "Why not plant a shorter-season variety? Then it might ripen perfectly adequately when trained to a taller height, and then you avoid the whole frost-risk problem or at least reduce the risk," he said. Battany's research is ongoing, and with advances in data loggers and the analysis of the information they gather, he expects future seasons to yield additional information that will help growers fine-tune vineyard management. "Some of the electronic measurement devices—the little data loggers—are really improving, greatly increasing what we can measure," he said. "We'll have so much more information to base our decisions on, and in real time." • Farming: Pass it on Succession Planning from Kibble & Prentice At Kibble & Prentice, we understand how important your farm's future is to you. Put the legacy of your land in our hands, and we will guide you through the steps to transfer ownership to the next generation. Our specialty encompasses navigating financial implications, family dynamics and management decisions. It's never too early to get started. Contact us for a consultation. 800.767.0650 Succession Planning · Employee Benefits · Commercial Insurance · Retirement Plan Services · Private Client Services GOOD FRUIT GROWER JANUARY 15, 2014 33

Articles in this issue

Links on this page

Archives of this issue

view archives of Good Fruit Grower - January 15