THE CATALPA SPHINX. 
these will be injurious to the leaves. In the preparation of these 
materials for spraying. the desired quantity of the chemical, usually 
1 pound of Paris green or 3 pounds of arsenate of lead to 50 
gallons of water, is weighed out and thoroughly mixed in a pail or 
other small container with a gallon or two of water. This mixture is 
then poured into a 50-gallon barrel, the remainder of the water added, 
and after having been strained through fine copper gauze for the 
removal of particles which might clog the nozzles, the spray is ready 
for use. 
The application of the arsenate of lead or Paris green spray in com- 
bination with Bordeaux mixture is desirable, since the foliage of the 
catalpa is frequently infected by leaf spot? and by other similar 
diseases which may be controlled by the application of Bordeaux 
mixture. Moreover, in the presence of Bordeaux mixture no burning 
is likely to result, even to the most delicate foliage, through free 
arsenic in the Paris green or arsenate of lead used in the spray 
mixture. Bordeaux mixture may be prepared for this purpose as 
follows: In a barrel containing 25 gallons of water hang 6 
pounds of blue vitriol or bluestone in a cloth sack. Four pounds 
of fresh stone lime should then be slaked in a pail or other 
container and water added until of about the consistency of 
whitewash. This mixture should then be poured into a second barrel 
with 25 gallons of water. In the usual preparation of spray mixtures 
50-gallon barrels are used. After the bluestone has dissolved and 
the lime has been added to its respective quantity of water the two 
barrels may then be raised and simultaneously poured into a third 
one, the mixture being well stirred at the same time. After the prepa- 
ration of the Bordeaux mixture according to this formula the requi- 
site amount of Paris green or arsenate of lead is added and thoroughly 
stirred into the mixture. 
A sprayer suitable for the control of the catalpa sphinx caterpillar, 
or other larve feeding on the leaves of catalpa or other trees of similar 
size and habit, might consist of one of the smaller power outfits such 
as are used in orchard spraying, or one of the large double-action 
hand pumps capable of furnishing a spray mixture to from three to 
five nozzles of the removable steel-disk type, using the large opening, 
at about 100 pounds pressure. 
With the aid of a 10 to 12 foot tower on the wagon and an exten- 
sion rod on the hose line, it will be possible to treat trees from 35 to 40 
feet in height, which is about the maximum for the ordinary catalpa 
under cultivation. For trees of greater height a three-eighths to one- 
fourth inch nozzle of the Worthley type, supplied by a pump capable 
of delivering from 30 to 50 gallons a minute at a pressure of from 300 
to 400 pounds, will be found necessary. Trees as much as 100 feet in 
1 Phyllosticta catalpae. 
