136 PEACH LEAF CURL*. ITS NATURE AND TREATMENT. 



made to cari\y out spraying experiments in western Oregon, so that 

 the needs of the growers west of the Cascades could be supplied. 



The great rainfall which annually occurs on the west side of the 

 Cascade Mountains makes the vegetation of that region especially 

 liable to fungous diseases, and the peach is no exception to this rule. 

 In the Willamette Valley, Oregon, along the lower Columbia, and in 

 the basin of Puget Sound in Washington, peach leaf curl has become 

 a great hindrance to extensive peach culture. In view of these facts, 

 many peach growers of Oregon and Washington were requested by 

 the Department to conduct experiments for the control of the disease, 

 and it was taken up by a number in 1894 and again in 1895. Several 

 of the gentlemen who conducted such work prepared reports of the 

 same, which should prove of much interest and value to the peach 

 growers of both States. 



Among those who entered heartily into the work was Mr. M. O. 

 Lownsdale, of Lafayette, Oreg. This gentleman conducted very 

 extensive spraying tests according to plans supplied by the Depart- 

 ment, both in 1894 and 1895, using in his work as many as 30 acres of 

 young peach trees in 1894. At the close of his experimental spray 

 work Mr. Lownsdale gave the following general facts respecting the 

 situation in the Willamette Valley, in which Lafayette is situated, 

 being the center of an extensive fruit-growing region of Yamhill 

 County: 



I hand j^ou herewith my report of experiments for the prevention of peach leaf 

 curl for the season of 1895, to which I desire to add a few words upon the status of 

 the peach industry in the Northwest. 



Peach growing has been abandoned to a great extent in the Willamette Valley 

 because of the attacks of the shot-hole fungus and leaf curl. Growers have not 

 understood the causes of their troubles, and have attributed them to peculiar climatic 

 conditions, or have grouped them under tlie indefinite term blight; but now that the 

 nature of these fimgous troubles is better understood, and the remedies suggested 

 have proved so efficacious, it seems that the abandonment of the industry may have 

 been premature. The success of the preHminary experiments has restored the con- 

 fidence of orchardists in a great measure, and as it becomes widely known that our 

 fungous troubles can be controlled, increased attention will be given to peach 

 growing. 



Experiments through a series of four years on a block of 6 acres of Early Char- 

 lotte peaclies indicate that it may be possible to prevent these destructive fungi 

 from getting a foothold in an orchard. This block of trees, which was planted in 

 dormant bud, has received an annual treatment in October and two treatments each 

 spring with the ammoniacal copper carbonate, with the exception of the spring of 

 1895, when your modified Bordeaux was applied. Neither leaf curl nor shot-hole 

 fungus has developed in this block. A fair crop of fruit was harvested this summer— 

 the fourth from the Ijud— and the trees are healthy and have grown luxuriantly. If 

 intending planters would select perfectly healthy trees— either yearling or (Ljrmant 

 buds— and would give them one treatment in autumn, as the Department has sug- 

 gested, in addition to the spring treatment for leaf curl, it is probable that peach 

 growing would again become profitalile in the Willamette Valley. I am convinced 

 that if the efficacy of the modified Bordeaux mixture for the control of leaf curl 

 hid been known five years ago the industry would have been flourishing to-day, for 



