Date: Sat, 22 Jun 2002 21:31:16 -0700
Reply-To: BB for Hummingbirds and Gardening for them in the Southeast <HUMNET-L@listserv.lsu.edu>
From: BB for Hummingbirds and Gardening for them in the Southeast <HUMNET-L@listserv.lsu.edu>
Subject: Re: [HUMNET-L] plants and feeders for Seattle area
To: HUMNET-L@listserv.lsu.edu

> In a message dated 6/21/02 1:40:25 PM Pacific Daylight Time,
> chriss@MICRONICS.NET writes:
>
> zone 8 [zone 5 Western Garden's gardening book and Sunset books--does
> anyone know the reason for the same area having two different zone
designations?],
>

HUMNETters,

Although this group started out rather parochially (pun intended) in
Lousiana, it now boasts members from the four corners of the USA. This is
a bewildering range of climates to keep track of, and it would
help all of us if each member would include his or her location (city and
state) as part of your signature at the bottom of each post.

Most e-mail programs have provisions for setting up multiple signatures so
you can just click on the one you want to use without having to type out
this information more than once. I have five different versions of mine,
which I choose, depending upon which hat I am wearing and the identity of
my intended correspondent.

Also, the climate where you live necessarily colors your experiences in
growing hummer plants and the advice you give to others. I strongly
recommend that each one of you include indications of your local climatic
conditions in your signature as well. In the USA, there are at least three
ways that we can evaluate the climate in which we live by using
standardized
zone maps:

1. USDA hardiness zone map.

This map is based purely upon average minimum temperatures. One can find
this map in various locations on the internet, but I prefer that of the
U.S. National Arboretum, which gives a good explanation of the factors
considered in the zoning:

http://www.usna.usda.gov/Hardzone/

2. The Sunset Zones.

Since the first decade of the 20th Century, Sunset Magazine has been a
prime source of information on travel, home building and remodeling, food,
gardening, etc. for the western half of the United States. Shortly after
WWII, Sunset published the first Sunset Western Garden Book. In a later
edition, they developed detailed climate zones for the western half of the
country (since revised and refined several times). This book (and its
later editions) has been the gardener's bible in the states from New Mexico
to Montana west for more than 50 years. In 1997 the climate zones were
expanded to cover the entire U.S. in the Sunset National Garden book.
There is also a Sunset Northeast Garden Book, and a Sunset Midwest Garden Book
was published early early in 2002.

The latest (7th) edition of the Sunset Western Garden book came out early
in 2001. I wrote or revised entries on more than 100 genera for the plant
encyclopedia, including everything from Aloe to Salvia, including Geranium,
Lavandula, Quercus, and many smaller genera.

Sunset's 47 climate zones (45 in the continental U.S., 2 in Hawaii) are
much more detailed than the USDA maps (which cover only average minimum
temperatures), taking climate characteristics down to very local levels.
Their calculations take into account six factors:

* DISTANCE FROM THE EQUATOR (latitude - locations farther from the Equator
experience longer, cooler winters)

* ELEVATION (higher elevations experience longer, colder winters and lower
night temperatures)

* OCEAN INFLUENCE (more ocean influence results in a more moist atmosphere,
milder winters, and specific rainfall patterns)

* CONTINENTAL AIR MASS INFLUENCE (locations farther inland experience
cooler
winters, warmer summers, and rain at all times of the year)

* MOUNTAINS AND HILLS (mountains and hills act as barriers that affect
weather patterns)

* LOCAL TERRAIN (warm air rises, cold air sinks)

A map and descriptions of each of the 45 continental U.S. Sunset Climate
Zones are available at the following URL:

http://www.homestore.com/LawnGarden/Zones/Climate/default.asp

3. The American horticultural Society Heat Zone Map.

The American Horticultural Society has developed a map that
records the average number of days per year with temperatures above 87
degrees F/30 degrees C. This measurement helps determine which kinds of
heat-requiring plants you can grow. This map is at:

http://www.suite101.com/userfiles/79/hz1024.jpg

There is a good explanation of this map at:

http://www.ahs.org/publications/heat_zone_map.htm

I think that all gardeners on the internet should set up their signatures
(as I have) with at least the USDA and Sunset zones. These very brief and
compact citations convey a great a great deal of information to your
correspondents and place your comments on plants and gardening into
contexts
which would otherwise require a great deal of explanation. If you have
trouble figuring out in which Sunset zone you belong, let me know, and I
will help you.

John MacGregor
South Pasadena, CA 91030
USDA zone 9 Sunset zones 21/23