"Fleemo" wrote in message
om...
Maybe Fleemo was referring to the California Energy Commission's 16
climate zones which, like Sunset's zones, are based on "temperature,
weather and other factors", but have no numerical correlation to
Sunset's zones. Used primarily to predict and track electrical
power
consumption for specific geographical areas. -Olin

Indeed, I was. So this has little connection to gardening? When
folks discuss zones in this newsgroup, are they referring to the
Sunset Western Garden book's definition of zones? Or are there other
zone definitions to take into consideration?

You make a good point in that if a zone is referred to, the zone type
should be specified. The USDA Cold Hardiness zones are used to indicate
plant sensitivity to cold temperatures. The AHS Heat-Zones indicate
sensitivity to heat. The Sunset zones are true climatic zones and
include other relevant factors such as humidity, pH, temperature,
exposure, wind, elevation, coastal influences, etc. The Monrovia
Nursery has a brief comparison of the USDA, AHS, and Sunset zones with
links to the zone maps at
http://www.monrovia.com/MonroviaWeb....8?OpenDocument
(The url may wrap)

The zone references are usually to the USDA zones. West of the
continental divide, the Sunset zones seem to be more useful.

Olin