SPRAYING PEACHES. iF 
sulphur wash for the control of the fungous troubles mentioned. 
Earlier experiments by the Bureau of Entomology had already 
shown that by the proper use of arsenate of lead the curculio could 
be largely controlled, though on account of danger of foliage injury 
its use had not been unqualifiedly recommended. Cooperative 
experiments between the two bureaus have shown that the fungicide 
and arsenical may be used as a combined spray with satisfactory 
results in controlling these troubles and without injury to the fruit 
and foliage of the peach. Hence, there is now available a satisfactory 
method for the control of these three serious obstacles to successful 
peach culture. 
In the following pages the brown-rot, peach scab, and curculio are 
treated with reference to their occurrence on the peach, and results 
are given of experiments and demonstrations in their control con- 
ducted jointly by the Bureau of Plant Industry and the Bureau of 
Entomology during 1910. The writers were assisted in this work by 
E. L. Jenne and E. W. Scott, of the Bureau of Entomology, and by 
Leslie Pierce and G. W. Keitt, of the Bureau of Plant Industry. 
BROWN-ROT. 
NATURE AND CAUSE OF THE DISEASE. 
Brown-rot is a fungous disease which affects the stone fruits, such 
as the peach, plum, and cherry, and to a less extent some of the pome 
fruits, such as the apple, pear, and quince, producing a so-called rot 
of the fruit and blight of the twigs. It is caused by a fungus known 
to botanists as Sclerotinia fructigena (Pers.) Schrét. Brown-rot is 
the common name usually applied to the disease, but monilia, the 
generic name of the imperfect stage of the fungus, is often used by 
some of the older fruit growers. 
The disease appears on the fruit as a small circular brown spot, 
which under moist, warm conditions enlarges rapidly, soon involv- 
ing the entire fruit in decay (fig. 1). The spots do not usually 
become sunken, and the fruit remains plump until almost entirely 
decayed. The fungus growing in the tissues of the fruit breaks 
through the skin, forming small, grayish tufts of spore-bearing 
threads. These tufts, although few on young spots, soon become so 
numerous as to give the diseased area a grayish, moldy appearance, 
which is responsible for the term ‘‘peach mold”’ sometimes applied 
to the disease. The spores which are produced in great abundance 
by these fungous tufts are blown by the wind and carried by insects 
and birds from fruit to fruit, tree to tree, and orchard to orchard. 
Finding lodgment on the fruit under favorable conditions of tempera- 
ture and moisture, these spores germinate, producing a fungous 
. 
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