Re: Other MYTHS
nstairs@advanstar.ag.uiuc.edu
Thu, 6 Aug 1998 08:55:19 -0500
My understanding is that "sunscald" occurs from increased temperatures of the bark which results in the cambium tissues being injured and killed. Under this assumption you would not necessarily observe "sunburn" on the leaves, and if it were solely a moistire availability issue I would expect to see drought indications in the entire crown not just on one side. The concept of sunscald is based on observations of trees showing dead bark and/or callus tissue. The question arose partly because of a pattern of damage on the southern sides of the trunks. If this were solely the result of physical injury from planting one would expect to see a broader distribution of the injury around the trunks. Sunscald is suppposed to be of more concern for thin barked trees and there may even be a relationship with respect to latitude and climate (I am guessing here). I have seen this type of damage but have to admit that I would be hard pressed to determine whether the injury occurred in the su
mmer or, as quite possib
le, in the winter (possibly places with cool/cold winters but sunny weather - another guess). You are digging up some Master's thesis ideas here - we really have a lot to learn about trees.
Nancy