12 LIME-SULPHUR PREPARATIONS FOR APPLE DISEASES. 
EXPERIMENTS IN ARKANSAS. 
At Siloam Springs, Ark., during 1909, Messrs. F. W. Faurot and 
EK. L. Jenne, of the Bureau of Entomology, conducted another set of 
experiments under the writer’s directions. The results of those 
experiments throw considerable doubt on both the efficiency and 
safety of the commercial lime-sulphur solution as a summer spray for 
apple diseases. The: Ben Davis, Shannon, Arkansas, and Elkhorn 
varieties were sprayed with several different strengths of the commer- 
cial preparation in combination with arsenical poisons. The self- 
boiled lme-sulphur solution and the Bordeaux mixture were also 
used. The trees were sprayed five times, as follows: (1) As soon as © 
the petals fell; (2) three weeks later; (3) eight to nine weeks after 
the petals fell; (4) two weeks later, and (5) three weeks after the 
fourth application. 
RESULTS OF THE TREATMENT. 
The trees sprayed with commercial lime-sulphur solution diluted 
to contain 1 gallon in 30 gallons of water, with the addition of the 
usual amount of arsenate of lead, showed very little or practically no 
foliage injury after the first and second applications; in fact, according 
to notes made on June 30 and July 22, no serious injury followed the 
third treatment, which was applied on June 2. After the fifth apph- . 
cation, however, the injury increased rapidly, and at picking time 
half of the leaves were on the ground. It seems that the injurious 
effect of the mixture was cumulative, the injury being increased 
by each application. Three applications would, perhaps, have 
resulted in little or no damage, but five sprayings were evidently 
more than the trees could stand. Considerable rain fell during May 
and June, but the remainder of the season was dry. The trees suf- 
fered severely from drought, which apparently exaggerated the spray 
injury. On account of the shortage of foliage on the trees a portion 
of the fruit was sunburned, but no russeting was caused by the spray. 
This sunburning also occurred on the fruit sprayed with Bordeaux 
mixture, but to a much less extent. 
The commercial lime-sulphur at a strength of 1 to 30 in combina- 
tion with Paris green began to burn the foliage soon after the first 
application was made, and by midsummer the trees were almost bare. 
Arsenite of lime was also used with the 1 to 30 solution, and the 
results were disastrous. The foliage was burned to a crisp and the 
fruit badly scorched by the first application. Even the new twig 
erowth was killed to a considerable extent. 
The self-boiled lime-sulphur and arsenate of lead caused no injury 
to fruit or foliage. The fruit sprayed with Bordeaux mixture was 
quite badly russeted and the foliage suffered considerable injury. 
[Cir. 54] 
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