Leslie Huffman, apple specialist at the Ontario Ministry of Ag and Food, posted a question to the listserv today about extreme temps and bud kill. I’ve pasted in some of the responses below. You may also want to check the OMAFRA Apple webpage at www.ontario.ca/apples
Stay warm, everyone!
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Apricot -25 F
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Folks
This is what I remember:
-40 F Â -40 C. kill apple trees
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Leslie and all,
Minimum temps and damage to buds for the fall/Winter/early spring are moving targets.
The Ontario Tender Fruit and Grape Marketing Boards hired KCMS and work with CCOVI at Brock University (Grape only) to post LT 10%, LT50% and LT90% at 2-3 week intervals throughout the dormant season.
The tender fruit is posted on the Ontario Tender Fruit Producers’ Marketing Board, but it has not been updated recently. I just mentioned that to the CEO of the Board and she is going to get it updated when one of her staff returns from vacation. I can send you the latest grape info from the website if you want.
Nothing going on with apples yet.
Wind machines have been on 3 times for grapes already this fall/winter and I would say it would be the same for tender fruits (peach, nectarine, plum, cherry, pear).
There have been some crazy spikes in the temps in Niagara – Dec 16-17 and Dec 24-25. Lows recorded on Dec 16-17 ranged from -14.8C at the lake and -25.1C on top of escarpment at Grimsby (mainly grape and apple area). Temperature inversions have been strong ranging from 1.6C to 9.1C at the 40-50 foot height (I suspect the 1.6C location is near the influence of a wind machine.
source – Vine and Tree Fruit Innovations (formerly Weather Innovations Network).
Dr. Richard Layne did some freezer work on peaches in the 70-80s for his screening of Harrow selections but not sure how many standards he did.
Hope this helps.
Ken Slingerland - Wind Machine Specialist
Lakeview Vineyard Equipment Inc.,
40 Lakeshore Road, RR5,
Niagara-on-the-Lake, ON L0S 1J0
Shop: 905-646-8085
Toll Free: 1-866-677-4717
Cell: 905-651-0057
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Jon Clements
aka JMCEXTMAN
413.478.7219
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