Connie,
The differences between zones 6b and 7a is minimal. Maybe a 5 degree or so
average winter temperature. This will not make much difference in
survivabilty of your plants. Rthese zones are based on AVERAGE winter
temperatures, so even though somone may be listed as zone 6b, for example,
they may have several zone 7-ish winters in a row.

To make things even more complicated.. the USDA is having to revise their
charts due to global climate changes.

Bottom line... You can grow both zone 6 and zone 7 rated plants with Zone 6
being more ....'surviveable'



"Boxwood Studios" wrote in message
oups.com...
That's the problem (thank you for posting the link): but it gives a
reading for Oklahoma City but not for Guthrie.

The zip is 73044; is there someplace I can plug in the zip?

Sorry if I'm not seeing it..

Connie