84 
THE GEAPE ROOT-WORM. 
arsenate of lead for spraying purposes and the sharper competition 
among manufacturers to secure the trade have been the means of 
considerably lowering its cost to the consumer and the matter of 
price should no longer be a bar to its use. 
COMBINING INSECTICIDES WITH FUNGICIDES. 
Since the use of a fungicidal spray for grapevines is highly desirable 
and frequently absolutely necessary to hold in check fungous dis- 
eases such as mildew and black-rot, and since some of the applica- 
tions for these fungous diseases and the insect pest may be made 
at the same date, it has become customary to combine the two 
treatments by adding poison in the form of arsenate of lead to Bor- 
deaux mixture, the fungicide used against the fungous diseases. 
The formula recommended for this combined treatment is asf ollows : 
Pounds. 
Copper sulphate (blue vitriol) 5 
Fresh stone lime 5 
Arsenate of lead 3 
Water 50 
When Paris green or arsenite of lime are the arsenicals used, 4 
ounces of the former, or 1 quart of the latter prepared according to 
Kedzie's formula, may be added to 50 gallons of Bordeaux mixture. 
For reasons given above the use of arsenate of lead in preference to 
either of these other arsenicals is strongly urged. We here include 
detailed directions for making Bordeaux mixture which are given 
by Mr. C. L. Shear, of the Bureau of Plant Industry, in Farmers' 
Bulletin 284, treating of fungous diseases of the grape. 
PREPARATION OF BORDEAUX MIXTURE. 
Failure to secure satisfactory results from the use of Bordeaux 
mixture is frequently due to lack of proper care and thoroughness in 
its preparation, or to the use of poor material. All ready-made 
preparations of Bordeaux mixture in the form of a paste or a dust 
should be avoided, as the chemical constitutents do not properly 
combine in these conditions. A definite chemical compound is desired, 
and this can only be produced in proper form and condition by care- 
fully following the directions given below: 
Stock solution. — In order to carry on the work with the greatest convenience and 
economy, a considerable quantity of copper sulphate and of lime should be ready for 
immediate use. The copper and the lime may be prepared and kept most conven- 
iently in the following manner: 
Copper sulphate solution. — Take 100 pounds of copper sulphate (bluestone), place 
it in a gunny sack, and suspend it in a 50-gallon barrel of water. Kerosene or whisky 
barrels will be found very convenient. The copper sulphate will all dissolve in from 
12 to 18 hours if suspended in a loosely-woven sack, but if it is thrown loose in the bot- 
tom of the barrel it will take several days and considerable stirring to dissolve it. Thia 
