hort.net Seasonal photo, (c) 2006 Christopher P. Lindsey, All Rights Reserved: do not copy
articles | gallery of plants | blog | tech blog | plant profiles | patents | mailing lists | top stories | links | shorturl service | tom clothier's archive0
 Navigation
Articles
Gallery of Plants
Blog
Tech Blog
Plant Profiles
Patents
Mailing Lists
    FAQ
    Netiquette
    Search ALL lists
    Search help
    Subscription info
Top Stories
Links
sHORTurl service
Tom Clothier's Archive
 Top Stories
Disease could hit Britain's trees hard

Ten of the best snowdrop cultivars

Plant protein database helps identify plant gene functions

Dendroclimatologists record history through trees

Potato beetle could be thwarted through gene manipulation

Hawaii expands coffee farm quarantine

Study explains flower petal loss

Unauthorized use of a plant doesn't invalidate it's patent

RSS story archive

light intensities and latitude

  • To: Multiple recipients of list <iris-l@rt66.com>
  • Subject: light intensities and latitude
  • From: storey@aristotle.net (J. Michael, Celia or Ben Storey)
  • Date: Fri, 21 Feb 1997 16:24:50 -0700 (MST)

I haven't yet seen latitude discussed here as a factor to consider when
shopping for iris sources, and I wonder if it should be.

NPR reported recently that a film student took a light meter reading out of
doors at noon on a clear, sunny day in New York, NY, and came up with a
reading of 300-and- some-odd candle feet. The same week, a film student in
Los Angeles also took a light meter reading outside on a clear sunny day,
and his clocked 700-and-something candle feet. (Sorry I don't recall the
exact data, I was driving.) NYC is located at 40 degrees, 43 minutes N; LA
sits at 34 degrees, 4 minutes N.
This is a monster difference in light intensity, especially for living
things whose food production depends upon how well they absorb and employ
light energy.

Although it's a perfectly logical observation, I had not considered how
dramatically different light *intensity* (not merely duration) might be in
different regions.

Is there literature about the "physics" of iris acclimation to growing
conditions? Are plants that survive in dimmer, northern climes less
ambitious and productive, or does something in their foliage respond more
efficiently to light? Do they adapt by doing more with less or just by
doing less? Are they more like high-speed photo films or more like
reptiles?

Does brightness  play a huge role in how well iris hybridized in one locale
do when transplanted into  another?

celia
storey@aristotle.net  USDA Zone 7b
Little Rock, Arkansas 34 degrees, 43 minutes N latitude... sorry I don't
own a light meter to report on our high-noon brightness, anyway  it's
raining






 © 1995-2015 Mallorn Computing, Inc.All Rights Reserved.
Our Privacy Statement
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index