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rest of the orchard became entirely bare by the 1st of August. It 
were thought at the time that five treatments were probably more than 
were necessary. The question then arose as to how few sprayings 
would be necessary to prevent the disease. It was deemed best, there¬ 
fore, in planning this experiment to take the standard fungicide and 
find the least number of treatments that would prevent the disease and 
the best times for making them. On account of the beneficial results 
from spraying the experimental trees in 1892, the owners decided to 
spray the whole orchard in 1893. In doing this the suggestions of the 
Department were followed quite closely and a record of the work was 
kept, so that it furnishes an interesting example of the success of the 
treatment and its cost when done on a large scale. 
The work, therefore, may properly be discussed under two heads, (1) 
an experiment to determine the least number of treatments with Bor¬ 
deaux mixture necessary to prevent leaf-bliglit, and (2) an experiment 
to ascertain the actual cost of treating a large orchard with Bordeaux 
mixture four times. 
TREATMENT TO PREVENT LEAF-BLIGHT. 
The plan of the first experiment was as follows: A portion of the 
orchard was selected which was uniform and where there were few 
missing trees. Eight plats of 20 trees each (two rows of 10 trees each) 
were laid off side by side and numbered 1 to 8. A control plat of the 
same size as the numbered plats, 2 rows wide and 10 rows long, was 
left at the beginning of the series, and another at the end. Continuing 
from the second control plat, 8 duplicate plats were laid off and num¬ 
bered l 1 to 8 l . A third control plat followed 8 1 . 
Plats 1 and l l were treated April 24, 1 treatment. 
Plats 2 and 2 l were treated May 1, 1 treatment. 
Plats 3 and 3 l were treated May 15, 1 treatment. 
Plats 4 and 4 1 were treated June 1, 1 treatment. 
Plats 5 and 5 1 were treated May 1 and 15, 2 treatments. 
Plats 6 and G 1 were treated May l.and 15 and June 1, 3 treatments. 
Plats 7 and 7 1 were treated May 1 and 15 and June 1 and 15, 4 treatments. 
Plats 8 and 8 l were treated June 1 and 15, 2 treatments. 
It was desired to determine the most critical time in the treatment 
of the disease by making one single treatment at different times and 
observing which one did the most good. The Bordeaux mixture used 
was the 50-gallon formula, 0 pounds of copper sulphate in 50 gallons of 
water, with enough lime to neutralize all the copper. To avoid com¬ 
plications only the single strength of the fungicide was tried, and the 
experiment was limited to ascertaining the dates and the number of 
treatments. The spraying was superintended by Mr. W. H. Berryman, 
the manager of the orchard. The first application was made just, after 
the trees had come apparently into full foliage, at which time no leaf- 
blight had yet appeared. The four treatments of plats 7 and 7 1 were 
given so as to be sure to prevent the disease, and the others were 
simply intermediates. 
