PEACH BROWN-ROT. 9 



way, a Erwin F. Smith, 6 Humphries r and Quaintance. d Various 

 other articles dealing principally with the treatment of this disease 

 have appeared in bulletins of the state experiment stations and of 

 the United States Department of Agriculture, and in agricultural 

 journals. 



Hygienic measures, such as the removal of rotting and mummied 

 fruits and the pruning out of diseased twigs, have been strongly 

 recommended for the control of brown-rot, and most writers have 

 advised spraying with dilute Bordeaux mixture; but only in rare 

 instances have these remedial measures been successful. In spite of 

 the fact that in a wet season when treatment is most needed Bordeaux 

 mixture and other copper compounds injure peach leaves and defoli- 

 ate the trees, nearly all the recent publications on the subject have 

 recommended spraying with these fungicides, the authors believing 

 that the benefit would more than counterbalance the injury. 



ECONOMIC IMPORTANCE OF THE DISEASE. 



With the possible exception of peach yellows, which kills the tree 

 outright, brown-rot has for years been recognized as the most destruc- 

 tive disease of stone fruits, such as peaches, plums, and cherries. It 

 also affects the apple, pear, and quince, but only in rare cases does 

 it become a serious pest on these pomaceous fruits. The disease is 

 well distributed over the United States, and in most of our humid 

 sections it has practically prohibited the commercial production of 

 the European plum and often destroys a large portion of the crops of 

 peaches, Japanese plums, and cherries. The average annual loss to 

 the peach growers of this country easily reaches $5,000,000. Quaint- 

 ance e estimated the loss in Georgia for the year 1900 at from $500,000 

 to $700,000. The number of bearing trees in that State has more 

 than doubled since that time and the brown-rot has not abated in the 

 least, so that a conservative estimate of the loss at the present time 

 with a fair crop of fruit set and under average brown-rot conditions 

 would be $1,000,000; in fact, the writers are convinced that the loss 

 during the past season, with only a third of a crop, almost reached 

 that figure. Similar losses occur in other Southern States, and the 

 more northerly peach districts are by no means exempt. Dr. Erwin 

 F. Smith / placed the loss on the Chesapeake and Delaware peninsula 



a Report, Commissioner of Agriculture, 1888, pp. 349-352. 



b Journal of Mycology, vol. 5, no. 3, 1889, pp. 123-134; also vol. 7, no. 1, 1891, 

 pp. 36-39. 



c Eighth Report, Massachusetts Agricultural Experiment Station, 1891, p. 213; also 

 Botanical Gazette, vol. 18, 1893, pp. 85-93. 



d Bulletin 50, Georgia Agricultural Experiment Station, 1900, pp. 237-269. 



« Bulletin 50, Georgia Agricultural Experiment Station, 1900, p. 245, 



/Journal of Mycology, vol. 5, no. 3, 1889, pp. 123-134, 

 21263— Bui. 174—10 2. 



