134 A MANUAL OF FORESTRY 



prevention of wounds, and the other in the removal of the 

 sources of infection. The former method is impracticable 

 except in the case of ornamental trees. Infected trees should 

 always be removed as soon as the disease is apparent. Usually 

 this will be soon enough to save part of the wood or lumber. 

 It is of no avail to destroy the fruiting bodies alone as the 

 fungus will continue to grow in the tree and produce other 

 punks. 



WHITE PINE BLIGHT. 



It is now plain that this injury is not due to any insect, and 

 apparently not to any fungus, but probably is caused by un- 

 favorable weather conditions, such as winter injury due to 

 extremely cold weather without much snow, or to extremely 

 dry summers, or a combination of the two. This blight is 

 characterized by the death of the end tips of the needles, from 

 one-fourth to one-third thereof turning a bright reddish brown. 

 Sometimes the whole needle dies, giving the tree a brown ap- 

 pearance, but the tip of the needle is always affected first. 

 Trees that have been attacked look as if they had been scorched 

 by fire. Young trees are more susceptible to this form of injury 

 than old ones. On young trees, often the needles will wither 

 and curl up much as if scorched, and very frequently the twigs 

 also are killed back. In Maine 1 in exposed localities, acres of 

 young trees which were apparently healthy in the fall of 1907, 

 were entirely dead by the last of May, 1908. Usually the 

 injury was confined almost entirely to the north and northwest 

 sides of the young trees. Injury here was not limited to pines, 

 but spruces, firs and other conifers showed the same trouble and 

 in the same manner. 



In most parts of New England the disease was first noticed 

 in 1907. It was particularly widespread during the summer of 

 1907, and many feared the pine forests were doomed. It was 

 thoroughly advertised throughout New England and many 

 young pine stands were unnecessarily cut. Few trees died, 



1 See Report of Forest Commissioner of Maine, 1909, pp. 22-24. 



