We live in USDA (1990) zone of 5b that Arbor Day optimistically now
classifies as zone 6. Indeed, I don't think the actual temperature in
the last three years has been below -12 (F). However, with the winds
we got over the last few days and nights, the adjusted temperatures
were easily in -20 to -25 (F), and that kind of cold wind is pretty
typical. That would put us the range for USDA 4b. With only a few
exceptions we've planted cold hardy apple varieties. There are a
number of varieties we might like to add if we thought they could
survive.
How much of a factor should wind chill be in estimating a micro-
climate zone? How did the USDA climatologists factor in wind chill
in creating hardiness zones?
John Henderson
Sage Hen Farm
Lodi, NY
[NAFEX] wind chill and hardiness zones,
John Henderson, 02/07/2007