r ) 250 THE GENESEE FAEMEE. { ^ 



IBartiriiltitrnl iepartmeni 



CONDUCTED BY P. BAREY. 



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CURLED LEAF IN THE PEACH. 



This disease, if so we may call it, has been, for four or five years past, assuming a 

 more and more serious aspect, so that cultivators around us here in Western N. Y., 

 begin to say that if it goes on as it threatens to do, and no remedy be discovered, we 

 =1ioi' . • -, be compelled to abandon peach culture entirely. This would certainly be a 

 great calamity, and it becomes every one who wishes to escape it, to investigate care- 

 fully the nature of the disease, with a view to the discovery of the real cause. We 

 have been looking anxiously for some new light on the subject among the journals of 

 the day, and find the following in a recent number of the Country Gentleman. 



" The curl in the leaf of the peach, which is generally supposed to have had a very unfavorable 

 influence on the young crop, has given rise to much speculation as to its immediate cause, and cold 

 weather, aphides, fungus, or mildew, and diseased sap, have been variously assignetl as reasons. 

 The cold weather-theory will not always apply, as the disease sometimes appears after a'continued 

 succession of warm days, and the first opening of the young leaves shows the symptoms when they 

 have never been exposed to a cool night. Again, the disease has often made its appearance when 

 no aphides could at any time be detected with the most powerful achromatic glass; and newly 

 opening leaves, exposed only a few hours to the fresh air, and on which no insect had ever set 

 foot, have shown incipient but imraistakable indications. The explanation by "diseased sap," ia 

 ' too general and indefinite — the fungus theory has more appearance of plausibility, but needs inves- 

 tigation and proof — and if correct, the fungus must be of inlernal growth, as the smooth and 

 shining epidermis of the leaf is quite unbroken when the curl first appears in the cellular tissue. 

 But whatever may be the cause, the best remedy, so far as discovered, is vigorous growth. We 

 have observed trees standing iu the corner of a hog yard, where they were copiously supplied with 

 manui-e, and as a consequence making a rapid growth, covered with deep green foliage, with 

 scarcely a vestige of the curl ; and a row of peach trees which had been very freely sliortened in 

 the past winter, by cutting off branches in some cases an inch in diameter, have sent out strong 

 new shoots, almost wholly free from the disease, and the trees are well loaded with young fruit." 



Now our opinion, formed several years ago, and strengthened by later experience, is 

 that the curl is produced by phanges of temperature too great for the delicate constitu- 

 tion of the peach. "It is a tree that vegetates early, and being usually and from 

 necessity planted in a light soil, its carliness is hastened and the sap gets into active 

 circulation, and young leaves are put forth long before the weather in our northern 

 climate becomes steadily warm. We all know how common it is to have warm genial 

 spring weather about the opening of the buds, when a sudden change comes and we 

 have probably a week or two of cold, rainy weather, with slight frosts probably, with 

 cold dry winds. This at once arrests the development of the young shoots and leaves ; 

 the sap becomes stagnant and diseased ; the bark is ruptured and gum oozes out all 

 over the younger parts ; the leaves, whether in an embryo condition rolled up in the 

 bud, or half or wholly expanded, become swollen and diseased ; then mildew attacks 

 them, as it is always ready to reign upon sickly or feeble vegetation, and with this 

 aphides and other insects : hence the opinions that mildew or insects were the cause of 

 the disease. 



1849, we think, was the first year that this disease appeared in Western N. Y., in a 

 serious form. That spring was cold and changable. 1850 was similar and the curl was 

 worse than before, and so has continued since. One strong argument, at least so we 

 regard, in favor of this view, is the fact that if we have fine weather at the opening 

 of the peach buds, wo have very little curl, and that immediately after a change to 

 cold the curl appears, and its severity is always in proportion to the intensity and 



