[NAFEX] new hardiness zone map; mistake

ethan roland eroland at gmail.com
Mon Feb 5 12:32:07 EST 2007

Actually, the Arbor Day Foundation released an updated hardiness zone
map in 2004, and then again more recently in 2006 - I learned about
both from HortIdeas (which is an excellent publication that y;all
should look into - $15 for a year!

I agree with someone's earlier comment that your specific microclimate
is important in understanding the 'hardiness' of any plant -- But
these new hardiness zone maps are an incredible snapshot of the
changing climate we live in. I use these maps whenever I teach --
especially the 'Zone Changes' map is an amazing visual representation
of what is happening.

HOWEVER, I would like to draw everyone's attention to what I believe
is a mistake in the NADF maps. I'll include below a longer email I
sent to NADF, but basically, on the 'Zone Changes' map they have
colored southeastern MA + cape cod as a '+2' area. On more careful
inspection (and looking at some older USDA maps), I think there was a
mistake in coloring on the 1990 map which led to an error in the
overall changes map.

Take a look at the email below... I was able to talk to some folks at
NADF, but no changes have been made yet. If you agree that this could
be a mistake, I encourage you to get in touch with the NADF and ask
them to make some adjustments changes -- I would like this valuable
resource to be as credible as possible!


National Arbor Day Foundation -

>I am an ecological design consultant deeply involved with agroforestry
 >and other systems of permanent agriculture. I would like to thank you
 >immensely for your work in creating and making available the new
 >hardiness zone maps - they continue to be a valuable tool for my work
 >and especially my teaching.
 >However, I would like to ask a question about a rather strange anomaly
 >on the 'Zone Change' maps for both 2004 and 2006. The area of
 >southeastern Massachusetts (including cape cod) is represented as
 >experiencing a wopping +2 change in hardiness zone -- one of the largest
 >on the map and the only coastal +2.
 >Given that the 2006 map lists this area as a Zone 7 implies that in 1990
 >it was a Zone 5, and this is what the 1990 map shows at first glance.
 >However, if you look more carefully at that 1990 map, it seems that
 >southeastern Mass does not match the surrounding zone-hardiness pattern:
 >It looks like it should be a yellow Zone 7, like Long Island and a
 >sliver of Connecticut. In fact, even though it looks like 'Zone 5', the
 >shade of green is slightly different from the rest of the Zone 5
 >colorations. Perhaps this 1990 map was miscolored early on, and has not
 >been corrected? Or was southeastern Mass really Zone 5 in 1990?
 >The 1990 USDA version (as I'm looking it in Dave Jacke + Eric
 >Toensmeier's Edible Forest Gardens Volume 1), shows the area as Zone 6a,
 >6b, and 7a... and an earlier May 1960 USDA map I have shows it as Zone
 >6b and 7a. What's going on?
 >I would greatly appreciate your response to this query -- the updated
 >hardiness maps are very important for the public to see, especially your
 >excellent Zone changes map and the climate trends it reflects. Hence, it
 >is  very important that these maps are correct and error-free -- I
 >haven't looked exhaustively, but I hope this is the only spot on the map
 >where such an anomaly has occured. Please let me know if I've made a
 >mistake, or if you are in need of another update!
 >Thanks again and I look forward to your reply..

Ethan C. Roland
(518) 610-1375

AppleSeed Permaculture
Design - Teach - Advise

Northeastern Permaculture Wiki

8th International Permaculture Conference, Brazil, 2007

" You can count the number of seeds in an apple, but you can't count
the number of apples in a seed" - proverb via Paul Krafel

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