North American Fruit Explorers mailing list at ibiblio

[Jason MacArthur <rotread@localnet.com>]

I am curious as to the mechanism by which cold damages recently pruned 
fruit trees, in my case apples.  Is there a growth response to the 
pruning cut which forms susceptible tissue?  Does this growth response 
happen even if temperatures remain cold or is it a warming cooling 
cycle which causes the damage? I have read that less vigorous 
rootstocks are more vulnerable- why is this?
	I foolishly went ahead and pruned my dwarf apples in late February, 
and now the temperatures are plunging below 0 F at night.  Should I be 
alarmed?  There is nothing I can do but wonder, which has led me to 
this question.