North American Fruit Explorers mailing list at ibiblio

[Sarah Kehler Ewing <skkewing@yahoo.com>]

I should have noted in my previous email that the trees are indeed painted on 
all sides of the tree because sunscald is often worse on the North side of 
the tree due to the sun reflecting off the snow back onto the tree.  If you 
have ever experienced snow blindness then you understand how well snow 
reflects!

Sarah 
zone 3
Edmonton, AB

> Yes it is.  In northern regions the sun is so low on
> the horizon all winter that it strikes the trees almost
> perpendicularly to their trunks.  The result is that
> the tree bark warms up and the sap gets flowing while the
> sun is on it and then the sap freezes when the sun goes down
> splitting the bark open.  A few repeats of this and
> your tree is very damaged.  Local Birch trees have been
> known to have 1" wide cracks that flow freely with sap in
> the spring, but for some reason it doesn't seem to bother
> them as much as it bothers the fruit trees.
> 
> I read in a very old fruit tree book that an alternative to
> painting tree trunks used to be merely planting the tree
> with a 23 degree tilt towards the sun thus preventing the
> perpendicular sun strike!
> 
> 
> Sarah 
> zone 3
> Edmonton, AB
> 
> 
> --- On Tue, 3/31/09, Matthew Oller <matthewoller@yahoo.com>
> wrote:
> 
> > Helene, I thought it was , also to
> > reduce cracking, from extreme temperature changes,and
> > primarily on the south sides of trees,no?, matt,peace
> > 
> 
> 
>       
>