THE PREVENTION OF PEACH LEAF-CURL 



In bulletin 1G4: of this Station, Dr. B. M. Duggar has given an 

 account of the appearance and life history of the fungus causing 

 leaf-curl of the peach, with the results of some very successful 

 experiments undertaken by him for its prevention. It was for the 

 purpose of farther testing these and other treatments on a connner- 

 cial scale that the experiments here recorded were planned. 



The Orchards Selected for Experiment. 



The orchards selected for the experiments have, taken together, 

 presented a variety of conditions of soil, moisture, and exposure, as 

 v*^ell as wide differences in the trees themselves. The Elberta variety 

 has been given the preference because of its well-known suscepti- 

 bility to curl, but Early Crawford, Hill's Chili, Brigdon, Mountain 

 Rose, Globe, Beer's Late, and seedling trees have also been included 

 in the experiments. Of these varieties, some trees have been young 

 and others old, some fruiting heavily and others entirely without 

 fruit, some isolated and some surrounded by trees of the same or 

 different varieties, some sprayed during the season of '98, but most 

 of them treated in '99 for the first time. 



The Season of 1899. 



The season of 1899 was a peculiar one and not very satisfactory 

 for experiments with leaf-curl. The weather in April and early 

 May was unusually bright and dry. The leaves were out much in 

 advance of the flowers and were very large when the petals fell. 

 The curl that appeared was doubtless developed for the most part 

 by the short season of cold, rainy weather that occurred about the 

 middle of May. There was little difference in varieties as regards 

 the abundance of curl, but individual trees showed marked differ- 

 ences. The worst cases of curl I noticed were on Yellow St. John 



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