North American Fruit Explorers mailing list at ibiblio

[nottke <nottke1@earthlink.net>]

Bob,

Thanks for the suggestion of hail, but in this case each plum had a 1/8 to
1/4 inch diameter circular spot at the bottom drip point of the piece of
fruit, regardless of its up/down orientation.
A couple local fruit growers speculated that air pollution was the cause -
we had a couple murky days at that time, with occasional drizzle that could
have gathered and washed pollutants to the bottom of the fruit, where it
was concentrated by evaporation.
Jim
========
"Did you have any hail storms when the fruit was just developing on the
trees?  We had a number of times where we had hail storms here this
spring, sometimes when the ground was completely covered with hail that
it looked from the distance like it had snowed.  After the hail I looked
at the fruit and there are dark spots where the hail had hit the fruit.
Just a thought for you.

Bob Hartman"

Jim Nottke
Pfafftown, NC 27040
Hardiness Zone 7A