124 



PEACH LEAF CURL! ITS NATURE AND TREATMENT. 



What little growth there is which is thus far free from curl is termi- 

 nal — very little healthy or comparatively healthy growth is seen from 

 lateral buds. As to fruit, I may say that much is dropping from the 

 curled side and little from the other." (Pis. XVI and XVII.) 



The work of thinning the fruit from the sprayed halves of these 

 trees was not conducted at the time the sprayed trees of the general 

 experiment block were thinned. The writer believes that the records 

 of the fruit thinned from these trees were not kept except for one tree 

 sprayed on one side with Bordeaux mixture. The fruit on the sprayed 

 half of this tree was thinned May 8, 1895, and amounted to 1,145 

 peaches, which weighed 23 pounds, or very nearly 50 peaches to the 

 pound. These peaches were very uniform in size and stuck tightly to 

 the limbs. If they could have grown to the usual size when picked 

 in the fall they would have given 381 pounds of fruit. No peaches 

 were thinned from the unsprayed half of this tree. 



The yield of the 6 trees was carefully determined by weighing and 

 counting the fruit from the sprayed and unsprayed sides of each tree 

 separately. The results of this work are shown in the following table: 



Table 33. — Yield of sprayed and unsprayed halves of trees. 



By the preceding table it is shown that the sprayed half of tree 1 

 bore 718 peaches, weighing 284.8 pounds, while the unsprayed half 

 bore only 40 peaches, weighing 14.3 pounds. In this case, as in the 

 case of the other trees of this series, the localized position and action 

 of the fungus of curl upon a tree is shown. The unsprayed half of 

 the tree suffered so severely from the disease that it lost 92 per cent 

 of its foliage and all but 14.3 pounds of fruit. This severe attack 

 on one side of the tree appeared to have no influence whatever over 

 the sprayed limbs of the other side, as the fruit on the sprayed half 

 was thinned of 1,145 peaches, lost but 2 per cent of its foliage, and 

 bore 284.8 pounds of as fine peaches as any in the orchard. On the 

 other hand, the full and healthy covering of foliage on the sprayed side 

 of the tree appears to have had no beneficial influence over the diseased 

 side. Had it had any well-marked l)eneficial influence the fruit of the 

 unsprayed half would have been retained, which was not the case. 

 The same local action of the disease, and the same local nourishing 

 influence due to the assimilative action of the healthy foliage may be 



