130 N. H. AGR. EXPERIMENT STATION [Bulletin 144 



stroma. Later in the season, numerous flask-shaped perithecia 

 are formed within the stroma, but opening on its surface. These 

 produce many club-shaped asei, each containing eight spherical, 

 brown spores. 



Treatment. The fungus seems to be dependent upon wounds 

 for entrance to the host tissue. The best method of treatment is 

 found in avoiding unnecessary injuries to the tree and in the 

 proper care of all wounds. All cankered limbs should be 

 destroyed. 



WINTER INJURY. 



The Avinter of 1906-1907 caused very serious injury in the 

 orchards of New Hampshire. The damage was especially great 

 in young orchards and in those situated on low ground. ]\Iany 

 trees were found to be entirely dead the next spring and others 

 had only sufficient vitality to put forth leaves on a few scatter- 

 ing limbs. As the summer advanced it was evident that many 

 trees that had appeared fairly vigorous early in the spring had 

 sustained serious injury, and leaves on one large limb after an- 

 other would wither and turn brown. Throughout the summer 

 of 1907, and even in that of 1908, trees continued to succumb 

 to the injuries received in the above mentioned winter. 



Upon examination of the injured limbs and trees it was found 

 that the cambium and the inner bark had been dead over large 

 areas from the beginning of the season. Such injuries sometimes 

 amounted to practically a girdling of the limb or trunk and the 

 portions beyond were soon starved. In other cases, where the 

 girdling was not so complete, the tree survived for several 

 months, and in some cases seemed to outgrow the effects of the 

 injury. As the summer of 1907 advanced, sunken dead areas 

 became quite common on the injured but living trees. The 

 living tissue at the margin of these dead patches made a very 

 unusual growth, pushing out over the injury and developing a 

 marked ridge around it, thus leaving it as a conspicuously 

 depressed area. The line between the living and the dead bark 

 was often marked by an open crack (Fig. 28). 



Various varieties of trees suffered from winter injury. The 

 Baldwin seemed to have been more susceptible than any other 

 variety of apple. The large number of cases of serious injury to 



