Old Wives, water droplets was FROST

Robt R Pries rpries@sbcglobal.net
Wed, 14 Nov 2007 07:22:44 PST
 I some of the posts there was speculation about water
droplets focussing sumlight and causing damage. As I
remember the old wives tales; their concern was about
water droplets setting on leaves in the middle of the
day in Spring or summer. I guess I need to verify that
with my wife. I believe there was also a warning that
water droplets should not set on leaves of African
Violets if the sun is coming through the window. I
sort of understand the last tale since African Violets
(Santipaulia)growing in a window on a winters day may
suffer chill damage from the rapid evaporation of a
water droplet as the sun hits it. Sunlight is directly
related to evaporation rates. This is how they
discovered that less sunlight strikes the ground today
then 50 years ago because evaporation rates have
fallen. The sun is still puting out the same amount of
light but the polution in the atmosphere now reflects
as much as 20% back to space before it gets to the
earth. I have wondered if this is having an effort on
plants that require high light intensity for growth.
But back to the water droplets. I don't remember any
wives tales that talk about water droplets focusing
light in winter.

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