60 PEACH LEAF CURL: ITS NATURE AND TREATMENT. 



by three applications of amnioniac-al copper carl)onate after the appear- 

 ance of the foliage. He had ])etter success, however, from ainiuoniacal 

 copper carbonate applied in late winter, before the swellino- of the 

 buds, followed by three applications of a weaker solution upon the 

 foliage. "This."' he says, "was a complete success." 



In Michigan the work in 1893 was very satisfactory. Mr. Charles 

 Youngreen, of AVhitehall. sprayed one row of peach trees before they 

 leafed out in the spring. He states^ that not one of the sprayed trees 

 showed curl, while the unsprayed trees were all affected. The follow- 

 ing year he sprayed the entire orchard and not a tree suffered from 

 the disease. At Shelby. Oceana County, several growers sprayed 

 with Bordeaux mixture with good success. Mr. R. Morrill, of Benton 

 Harbor, stated at a meeting of the Michigan Horticultural Society 

 held at Shelby. June 14 and 15, 1893, that he found there, in four or five 

 cases, that men had sprayed peach trees with Bordeaux mixture, and 

 the effect in decrease of leaf curl was plain to be seen.^ Mr. Morrill 

 fails to state, however, whether the first spraying was done while the 

 trees were dormant. The effects of curl at Shelby at that time were 

 marked, the same gentleman remarking that in one morning he had seen 

 enough damage done l)y it to pay for spraying all the orchards within 



five miles. 



Professor Taft reports his work in 1893 as follows :=' "In order to 

 secure definite knowledge upon' the subject [treatment of curl], I 

 arranged for a series of experiments, and in the fall of 1892 had a 

 number of peach trees sprayed with a solution of copper sulphate 

 (1 pound in 25 gallons), and in a similar experiment at South Haven 

 Bordeaux mixture was used as soon as the leaves dropped in Novem- 

 ber, 1892. During the first half of April. 1893, the same trees were 

 again sprayed with similar mixtures, and other trees were treated that 

 had not been sprayed in the fall of 1892. The result was that where 

 fully 50 per cent of the leaves and all of the fruit dropped from the 

 unsprayed trees, there was little injury to the same varieties that were 

 treated in both fall and spring or that were sprayed only once, in 

 April; but where they were not sprayed until after the leaves had 

 come out only a slight benefit was secured. The results were given 

 in Bulletins 103 and 104 of the Station. On June 14, 1893. I gave the 

 results, up to that time, at the meeting of the State Horticultural 



Society." 



The' orchards of the Michigan Agricultural Experiment Station at 

 South Haven, in charge of Mr. T. T. Lyon, had suffered severely from 

 curl in 1890, 1891, and 1892.^ Mr. Lyon says, respecting the spray 



1 Letter dated Whitehall, Mich., Sept. 6, 1899. 



2 Kept. Mich. State Hort. Soc, 189.3, p. 68. 



3 Letter dated Agricultural College, Mich., Aug. 30, 1899. 



*See Repts. Mich. Hort. Soc, 1890, p. 144; 1891, p. 228; 1892, pp. 160, 161. 



