46 BULLETIN 395, U. S. DEPARTMENT OF AGRICULTURE. 
Supplementary notes by Mr. Waite follow. 
Notes supplementing Table IX. — This list gives most of the commonly grown com. 
mercial peach varieties of the Middle States in their order of ripening, and compara- 
tive estimates of scab injury to unsprayed fruit, in percentage of the value of the 
crop, in average localities from southern Pennsylvania, Maryland, and Virginia west 
to Missouri and Arkansas. North of this section, and particularly along the northern 
limit of peach culture, from New England and New York to Michigan, there is con- 
siderable reduction in the severity of the disease. The damage is distinctly less on 
light, sandy soils than on heavy soils or even on sandy loams. It is greatly reduced 
at high altitudes. For example, Bilyeu, before the advent of spraying, was consid- 
ered wholly unfit for commercial planting below 1,500 feet altitude in the Appalachian 
Mountain belt, on account of its susceptibility to scab, but could be grown successfully 
at high altitudes. The disease is somewhat more destructive in the Southern States 
than in the Middle States, and is generally aggravated in moist localities. In arid 
regions it disappears. 
A peach half covered with confluent scab spots, particularly if cracked open, may 
be considered as without commercial value. A peach badly spotted, with only 
one-fourth of its area covered, may be considered as of only 50 per cent commercial 
value in comparison with perfectly smooth fruit. Fruit with even less scab in a sea- 
son of low prices may be rendered unfit for marketing. With unsprayed trees of 
Heath, Salway, Bilyeu, Tennessee, and certain seedlings in lower altitudes in the 
Middle and Southern States it is not rare to have the entire crop rendered commer- 
cially worthless by scab. 
CONTROL MEASURES. 
SPRAYING. 
Since the serious economic aspects of peach scab began to be recog- 
nized during the early period in the development of Bordeaux mix- 
ture, when this newly discovered fungicide was being applied with 
such marked success in the control of many of the most destructive 
plant diseases, it is not surprising that the earliest efforts to control 
this malady consisted almost entirely of spraying experiments with 
Bordeaux mixture of various formulas. Cobb (1894, p. 386) and Stur- 
gis (1897, p. 271), apparently on a priori grounds, suggested treat- 
ments with this fungicide, while Price (1896, p. 840-841) reported 
decidedly favorable results from three applications of Bordeaux 
mixture (4-5-50) upon Early China and Mamie Eoss. Selby (1898, 
p. 237-260), in 1895 and 1896, earned out the first extensive spraying 
experiments, reporting favorable results from the use of Bordeaux 
mixture. Five years later the same author (1904, p. 67), as the 
result of seven years' study, states — 
For scab prevention, in addition to one spraying before blossoming with some 
effective fungicide, recent observations indicate the need of two applications of weak 
Bordeaux mixture [2-2-50] upon trees in foliage; the earlier of these to be made in 
northern Ohio about June 15; the second, three to four weeks later. 
Although this treatment was efficacious and proved satisfactory in 
certain sections and under certain conditions, so much host injury 
resulted that Bordeaux mixture never came into general use through- 
out the United States as a summer spray for the peach. 
