202 THE PLUM CURCULIO. 
SPRAYING PEACHES WITH ARSENICALS. 
Until within recent years comparatively little experimentation 
has been done with arsenicals for the control of the curculio on the 
peach. During the past five or six years, however, the subject has 
received attention at the hands of different investigators, and suffi- 
cient data have been accumulated to indicate about how much pro- 
tection may be expected. 
Paris green and London purple were undoubtedly early used on 
the peach, beginning with the first employment of these arsenicals 
against this insect. It was soon noted, however, that the foliage of 
peach was more sensitive than that of other deciduous fruits, and 
for this reason spraying of peaches seems not to have been practiced 
to any great extent. This foliage injury from arsenicals had been 
frequently commented upon and was pointed out by Dr. Forbes in 
1888 and 1889, and also by Prof. Weed, who gave experience of a 
Marion County, Ohio, fruit grower, as follows: 
We accidentally stumbled over the fact that from 60 to 70 gallons of water to one- 
half pound of poison in solution was strong enough to fully check the curculio and 
all or more than the peach tree would stand. We destrcyed a plum tree and several 
peach trees with our experiments, and know that 100 gallons to 1 pound of poison in 
solution is too strong for the foliage of some varieties of apples and that it will kill a 
peach or plum tree. My own opinicn is that one-half pound of poison to 60 gallons 
is safe, and if applied at the time of the usual bloom of apple and the second time 
10 days later will destroy the leaf-eating insects and the codling moths, but for plum 
and peach one-fourth pound to 40 gallons of water is strong enough and will, if applied 
twice, effectually check the ravages of the curculio without destroying the foliage. 
Despite frequent serious defoliation of trees some peach growers 
undoubtedly continued the use of Paris green and London purple, 
especially in the Northern States. In the South comparatively 
little spraying was done, so far as available records indicate. The 
control of the curculio on peach was therefore largely limited to the 
practice of jarring, and this work was not very generally followed, 
the insect being allowed to continue its depredations unchecked. 
With the increase of commercial peach culture in certain of the 
Southern States, notably in Georgia, and in view of the favorable 
conditions for the multiplication of the pest, its injuries became 
especially serious, not only on account of the fruit destroyed by it, 
but by reason of the prevalence in that section of a serious fungous 
disease of the fruit at about ripening time, namely, the so-called 
brown-rot, which the work of this insect, by its punctures, greatly 
favored. 
Considerable attention has been given during recent years to 
determining, if possible, ways in which Paris green and also copper 
fungicides may be safely used on the peach, notably by Messrs. 
