VOLUME VII. ) 
No. 4. S 
JOURNAL OF MYCOLOGY. | Aug. 15, 1894 
TREATMENT OF PEAR LEAF-BLIGHT * IN THE ORCHARD. 
By M. B. Waite. 
[Plates XXXII, XXXIII.] 
The experiments here described were carried on in the orchard of 
the Old Dominion Fruit Company, on the James Eiver, near Scotland, 
Ya. This orchard consists almost exclusively of standard Bartlett 
pears and contained originally 22,000 trees, of which at least 16,000 are 
still standing. The trees are now 19 years old and the greater part of 
them are in fairly good condition, except for pear leaf-blight, which for 
several years past has defoliated the trees during the month of July. 
This defoliation in midsummer deprives the trees of the use of their 
leaves during half of the season, and no doubt seriously interferes 
with their vigor. The cultivation has been fairly good. The trees 
were headed very low, and the lower branches, until the past season, 
extended nearly to the ground, but during the past winter they have 
been trimmed up. Most of the trees do not make a very strong growth, 
nor do they continue to grow long into the summer. Only occasionally 
does the general growth of twigs on a tree exceed 1 foot, and often it 
is much less. The fact that these trees have been regularly defoliated 
with leaf-blight made this an excellent place for experiment, particu¬ 
larly because of the availability of uniform blocks of similar trees. 
The appearance of the disease in question year after year to about 
the same extent makes it an easy one to experiment upon. In 1892 five 
sprayings with the 50-gallon formula of Bordeaux mixture entirely 
prevented the leaf-blight. The dates of the sprayings were April 28, 
May 15 and 30, and June 14 and 29. At the time of the first treatment 
the young leaves were just fairly expanded. The object of the spray¬ 
ings was simply to prevent the disease on about 160 trees as a part of 
another experiment of an entirely different character. The spraying 
was thoroughly done and the treated trees held their leaves to the 
close of the season and showed scarcely a spot of leaf-blight, while the 
Entomosporium maculatum Lev. 
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