18 PEACH LEAF CURL". ITS NATURE AND TREATMENT. 



Main Island, the peach curl seems to be prevalent only in the northern 

 provinces. * * * i gent letters of inquiry relating- to this question 

 to the graduates of our college, who studied especially about the 

 parasitic fungi in our laboratory, and whose opinions I can trust. 

 From ]Mr. Y. Takahashi, at Morioka, in Rikuchu Province, I received 

 the following answer : ' Peach curl is very prevalent in this town. 

 Almost every tree is more or less attacked by the fungus. I saw some 

 trees entirelj^ attacked. At the end of summer [spring?] all the dis- 

 eased leaves fell to the ground and new leaves were produced.'"- In 

 the southern island, Kumamoto, a correspondent reported to Professor 

 Miyabe that the disease had not been seen there Ijy him. From Tokyo 

 Professor Shirai, of the College of Agriculture, reports that he has 

 not yet found the disease in that section of the main island. 



In China, as the writer is informed, peach leaf curl prevails to a 

 very large extent, and the losses are probably considerable from this 



cause. ^ 



ORIGIN OF THE DISEASE. 



The countr}" of origin of peach leaf curl is not positively known. 

 It was hoped that the inquiry as to distribution would develop posi- 

 tive information respecting this point, but such has not been the case. 

 That seedling peaches are remarkably susceptible to the disease, and 

 that the Chinese Saucer peach is among those most subject to it, 

 appears to indicate that the home of the peach is the source of the 

 disease, and that the two may have come to us together from a com- 

 mon point of origin. Recent studies have been constanth^ tending 

 to reduce the number of species of plants once thought to be subject 

 to curl. At present it is believed that it is confined almost wholly to 

 the peach or its derivatives, as the nectarine and peach-almond. The 

 exceptions to this, where the disease has been noted on the plum, 

 almond, etc., are rare, and not sufficiently numerous or general to mate- 

 rially affect the evidence that the peach is the natural host of the fungus. 

 Thus far, however, it has been impossible to learn if the peach in the 

 interior of China, its supposed home, is affected by this trouble, though 

 in the coast regions it is said to prevail extensively. Such information 

 as has been obtained from Japan indicates the recent introduction of 

 the disease in that country, and that the United States is probabl}^ its 

 source rather than the near-by continental coast. In Australia, how- 

 ever, this may properly be questioned, for, as already mentioned, ]Mr. 



^Letter from Augustus White, Esq., forwarded April 3, 1896, through the kindness 

 of Mr. Rufus S. Eastlack, then U. S. Deputy Consul-General at Shanghai, China. 

 Mr. White says, in concluding his statements, that the Chinese, ignorant of the ase 

 of the knife in pruning, trust solely to an annual inspection of the trees at the time 

 the blossoms set, Avhen they carefully pick off all excess of fruit, and with it all 

 diseased leaves, etc., l>ut allow these to fall to the ground and remain under the 

 trees to rot or reproduce the plague, as nature thinks best. 



