1910.] PUBLIC DOCUMENT — No. 31. 65 



SUN SCORCH OF THE PINE. 



BY G. E. STONE, 



Much interest, accompanied bv an nnnsnal anionnt of alarm, 

 has been felt since 1905 in the so-called " pine blight," and, as 

 is customary where more or less conspicuous injury to trees 

 occurs, exaggerated reports have been made concerning it. This 

 blighting of the pine is not new to Massachusetts as we have 

 noticed it for at least twentv-five years. About twelve vears 

 ago it was quite prevalent in the eastern part of the State, being 

 noticed by us and reported by others. Prof. B. M. Watson of 

 the Bussey Institute and others have recently called our atten- 

 tion to a similar burning which occurred apparently at the same 

 time. 



Sun scorch of conifers in general is of common occurrence. 

 Pines growing in very dry situations are often sun scorched, and 

 frequently show yellow, inferior foliage ; the needles are some- 

 times burned, and it is not unusual for fungi to attack the dead 

 needles, but these fungi are never the primary cause of the 

 trouble. This condition of the pines may be found here and 

 there almost any season, but is more noticeable some seasons 

 than others. 



The present pine blight dates back to the winter of 1902-03, 

 when the conditions were such as to cause much injury to vegeta- 

 tion in general. The following winter, that of 1903-04, was 

 even more severe in its effects on vegetation, and caused exten- 

 sive root killing of many trees and shrubs. The pine, as well 

 as other trees, in many cases was killed outright, but the injury 

 to the pine was largely confined to the smaller roots, or those 

 less than /46 of an inch in diameter. It was not, however, until 

 the very dry summer of 1905 that extensive burning was 

 noticed, and this was very general throughout the State. The 

 season of 1905 was the first to attract attention to this burning 



