258 EXPEKIMENT STATION RECORD. 



be a serious pest to various trees. On this account an article by G. 

 Massee on a similar disease of the trees of New Zealand is extensively 

 quoted. 



As preventive measures it is suggested that the mycelium, which 

 travels through the soil, may be isolated by digging deep, narrow 

 trenches about the trees, care being taken to throw the excavated soil 

 toward the tree instead of from it. A second method, which has 

 proved of service in France, is to lay the trunk bare as far below the 

 surface of the soil as can be done without injury to the tree and to 

 cover the exposed trunk and soil with sulphur. 



The bro-wn spot of the apple, L. R. Jones and W. A. Orton ( Ver- 

 mx))ii fSfd. I\i>t. 1S99, 2)j.>. 159-16 Jf, j)^- !)• — In the Annual Report of 

 this station for 1891 (E. S. R., -1, p. 471), attention was called to a fruit 

 spot of the Baldwin apple which at that time was thought possibly to 

 be due to a fungus which was determined as DotJddea pomigena. A 

 re-examination of these brown spots has led to the conclusion that the 

 disease is not primarily due to a fungus. In the past season numerous 

 specimens of Baldwin apples have been examined. Beginning with 

 the first evidences of fruit spot in the autumn before harvest, a careful 

 search was made for bacteria and fungi, neither of which were found. 

 In connection with these observations it was determined that while the 

 spot is the worst in the case of the Baldwins it is also quite couuuon 

 on Northern Spy and was observed on Greenings. The spots are not 

 uniforml}^ distributed over the surface but are more numerous toward 

 the apical portion of the fruit. They are not confined to the surface 

 but appear at various depths, the deep ones often being overlaid by 

 a half inch or more of sound flesh, and are associated in their distribu- 

 tion with that of the vascular bundles occurring at or near the ends of 

 the veins which permeate the flesh of the fruit. 



An examination of the literature led the authors to conclude that 

 this disease is the same as that described by Wortmann^ under the 

 name of "stippen." This work is reviewed at some length and the 

 characters of the disease are summarized. Its occurrence is rather 

 widespread and, while preeminently occurring in the Baldwin apple, 

 more than 30 other varieties are reported as having been attacked to 

 some extent. The greatest damage done by this disease is in the 

 appearance of the fruit, although at times a slight bitter flavor is said 

 to accompany it. The author states the conclusions of Wortmaim that 

 the disease is a result of the concentration of the sap following a loss 

 of water. Several factors enter into the problem of spot formation. 

 Among them are the amount and rapidity of transpiration, the kind 

 and relative amount of substances in solution in the sap, the con- 

 ductivity of the tissues of the fruit, and the specific resistance of the 



iLandw. Jahrb., 21 (1892), pp. 063-675. 



