l86 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



TWO APPLE-LEAF TROUBLES NEW TO MAINE. 

 W. J. Morse. 



In the summer of 191 5 two foliage troubles of the apple were 

 observed, of which there appears to have been no previous rec- 

 ord in this state. One of these, which the writer has called 

 chlorosis, was widespread and common in a single orchard 

 and occurred to a certain extent on individual, scattered trees 

 in the same locality. No definite cause could be assigned to 

 the condition. The other, a disease previously reported in 

 Europe, Canada, South Africa and New Zealand, is known as 

 silver-leaf and was found to be fairly common in various parts 

 of the orchard growing section of the State. 



Chlorosis. 



In September, 1914 some diseased apple leaves were received 

 through the college of agriculture from their extension repre- 

 sentative in Franklin county, Mr. W. M. Morse. At that time 

 the trouble was known to exist on a single tree, growing by the 

 roadside in Livermore Falls. Further observations by Mr. 

 Morse in the spring and early summer of 19 15 showed that 

 this condition of apple foliage had a wider distribution than 

 was first indicated, and led to a visit to the locality by the writer 

 under his guidance. 



As far as observed this chlorotic effect on the leaves was 

 limited to apple trees in a rather restricted area of adjoining 

 portions of the towns of Jay and Livermore. Although several 

 more or less isolated affected trees, including Baldwin, North- 

 ern Spy and Harvey varieties were seen which were growing 

 on high, well-drained land under good conditions, observa- 

 tions in Jay were confined principally to a single orchard of 

 Baldwins of two or three acres in extent. This orchard was on 

 rather low land, naturally moist, but was fairly well drained 

 with open ditches. The leaf trouble was restricted to no par- 

 ticular part of the orchard but was apparently not quite so 

 severe on the higher portion. However, the trees here were 

 somewhat younger than the rest. The majority of those af- 

 fected were probably 25 to 30 years old and may have been 

 older. While they had apparently been neglected up to a few 

 years ago their treatment in this respect did not differ from 

 that given to the trees .in many other orchards in which no 



