Over the last nine years here near Simcoe, Ontario, McIntosh reach full bloom at 245 DD from Jan. 1 using base 5 celsius (41degrees). Temperatures are recorded hourly using a Hobo datalogger. It has varied from 225 to 260 although some of that variability is the guy making the full bloom call.
Harold Schooley Schooley Orchards Simcoe, Ontario, Canada _____ From: [email protected] [mailto:[email protected]] On Behalf Of Bill Shane Sent: Thursday, April 01, 2010 9:02 AM To: Apple-Crop Subject: Re: Apple-Crop: degree days and apple bloom prediction Con, This is degree day base 42 F. Bill On Thu, Apr 1, 2010 at 5:13 AM, Con.Traas <[email protected]> wrote: Sorry Bill, Degree days on what degree base? Con In Michigan we have used approximately 284 DD42 from March 1 as the start point for king bloom on Macs. This is in our Michigan State University Fruit Management guide E-154, from a chart originally prepared by Phil Schwallier of MSU. This is based on pre-1990 weather data in the Grand Rapids area of Michigan. In recent years we have been getting more DD before March 1....so ignoring what happens before Mar 1 is now becoming problematic. So, I generally add on 25 DD42 to the total and use a target of 310 DD42 from January 1 as the start point for king bloom for Macs. Not sure if this works for your area. 1/2" green is approx 205 DD42 from March 1, or 230 DD42 from January 1 with my fudge factor. Bill Shane -- Bill Shane District Extension Educator SW Mich Res & Extension Center Michigan State University 1791 Hillandale Rd, Benton Harbor, MI 49022 269-944-1477 x 205; 269-208-1652 cell No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.791 / Virus Database: 271.1.1/2781 - Release Date: 03/31/10 14:32:00
