IS THERE A CONNECTION BETWEEN THE BIRCH DIEBACK AND THE MARCH THAW OF 1936?

Abstract

The uniformity of birch dieback over the large area affected makes it unlikely that a general change of temperature or a moisture deficiency can be the explanation. However, damage caused by abnormal winter temperatures can strike with great uniformity. Such an abnormal condition occurred in the March 1936 thaw with a striking correlation between the area of the dieback and that of the thaw. It is suggested that a critical study of fact may be useful in arriving at an explanation of the cause of the dieback.Dr. Peder Braathe, of the Norwegian Forest Research Institute, Vollebekk, Norway, spent the year 1955-56 as National Research Council Fellow at the University of New Brunswick. In his travels over the northeastern part of the continent he was struck by the extent and uniformity of birch dieback damage and this led to his investigation and suggestion on this matter.