48 BULLETIN 395, TJ. S. DEPARTMENT OF AGRICULTURE. 
nate of lead, without serious injury to the host; and (3) that sulphur 
paste may control this disease. 
The purposes of the writer's experiments were (1) to test further, in 
relation to locality, season, and variety, the excellent spray schedules 
worked out by Scott and others; (2) to test the efficiency and desir- 
ability of a sulphur spray in comparison with self -boiled lime-sulphur : 
and (3) to correlate with control measures a clearer understanding of 
the nature, cause, and development of the disease. 
The spraying experiments 1 were conducted in commercial orchards 
at Cornelia, Ga., in 1910, 1912, and 1913, and at Hart, Mich., in 1911. 
More than 150 plats, containing over 10,000 trees, were sprayed, 
while parallel observations were made upon commercial orchards 
containing in the aggregate many hundred thousand trees. 
In the experiments of 1911, 1912, and 1913, the spray was applied 
by means of a gasoline power sprayer, double "'Friend' 7 nozzles being 
used. At Cornelia, in 1910, good barrel outfits were employed. 
Careful field observations of each plat were recorded throughout 
the season. At harvest time, in as many cases as was feasible, the 
fruit from a number of typical trees of each plat, usually 10 to 12, was 
picked, critically examined, and classified according to the occurrence 
and abundance of scab, the occurrence of brown-rot, and the salability 
of the fruit. By carefully noting many thousands of fruits in this 
fashion and tabulating the resulting data, it was possible to arrive 
at strikingly accurate and concrete comparisons of the efficiency of 
the different treatments. 
Experiments in 1910 and 1911. 2 
The season of 1910 in northern Georgia was very favorable for the 
development of scab and brown-rot and offered a severe test of the 
efficiency of the various treatments used. The results were emi n ently 
satisfactory, but since they have been reported in brief by Scott and 
Quaintance (1911, p. 23-26), they will not be considered further here. 
In 1911 extensive experiments were conducted at Hart, Mich., 
on 10 of the more important commercial varieties of that section. 
Owing to an unusually dry spring and summer, so little scab occurred, 
even upon unsprayed trees, that little differentiation of results of the 
various treatments was feasible. Even under these conditions, how- 
ever, the sprayed fruit appeared to be sufficiently superior to that of 
the control plats to justify the expense of the treatments. These 
results will not be considered further in this connection. 
1 Grateful acknowledgments are made to Messrs. A. M. Kitchen, Cornelia, Ga. (1910), H. W. Gebhart 
and F. Brooker, Hart, Mich. (1911), A. B. Veeder, S. R. Christie, and Laing & Segers, Cornelia, Ga. (1912), 
and W. B. Hunter, Cornelia, Ga. (1913), for their cordial cooperation. 
2 These experiments were conducted under the direction of Mr. W. M. Scott, formerly Pathologist. Office 
of Fruit-Disease Investigations, Bureau of Plant Industry, U. S. Department of Agriculture. 
