237 



the tendency is to put out these laterals. These sprouts are 

 almost always infected and quickly girdled, so in late fall or 

 winter, a tree with suspicious persistent leaves and burs in the 

 top and leaves on lateral shoots, is very apt to be infected. 



As was said, apparently most infection started at the tops 

 of the trees as evidenced by the appearance of the leaves, etc. 

 Yet many large trees were found to be infected upon a careful 

 tree to tree examination, at the base, and the only visible out- 

 ward sign of the blight was the reddish yellow pustules, forming 

 in the deep fissures of the bark, where the new inner bark is 

 breaking through. Upon cutting into this region, the diseased, 

 discolored inner bark next the wood was found filled with the 

 mycelium of the fungus. 



On old trees it takes more time for the disease to appear on 

 the outer surface of the bark in the form of pustules, and often 

 a. well defined blister of mycelium is found on the inside of the 

 bark showing no sign of its presence on the outside. For this 

 reason the complete peeling and burning of the bark on the 

 trunk of a tree that is going to be used is essential. 



In the inspection work that was carried on, specimens show- 

 ing the blight in various stages and under different conditions 

 were found, and among them, one in particular is worth men- 

 tioning. A large blister nearly a foot in diamter was discovered 

 and a great many of the pustules were rubbed off or destroyed. 

 All over the surface of the lesion were numerous holes made 

 apparently by wood-peckers, probably in search of the insect 

 larvae that are commonly found under dead bark. Is it not 

 possible for these birds to get spores on their feet and bills, 

 carry them to other trees which may not be infected, and upon 

 searching in that bark for more insects, thus deposit spores 

 of the blight? 



The infections found in the park numbered thirty, twenty-nine 

 of which are in the part that has been allowed to go without 

 management of any kind. In the first inspection made of the 

 park last fall only three or four trees were found to be infected. 

 Accordingly, on finding so much infection here it was decided 

 to make a careful strip survey of the bench land lying between 

 the State reserve on the north side of Bald Eagle Mountain, 

 and the Susquehanna river. The tracts are mostly farmers' 



