THE COMMON CABBAGE WORM. 11 
ARSENATE OF LEAD. 
As a result of the abnormal conditions incident to the European 
war, there is a scarcity of Paris green, which has naturally increased 
the cost. Arsenate of lead, however, which has been rapidly super- 
seding Paris green and other arsenicals as an insecticide, has not 
increased proportionately in price, and for many reasons is preferable. 
It has the advantage of being less harmful to growing plants and 
adheres better to the foliage, is less apt to burn the leaves of delicate 
plants, and is less troublesome to prepare. It serves the same purpose 
as Paris green and is applied in the same manner. It is sold both 
in paste and in dry powder form. Two pounds of dry lead arsenate 
to 50 gallons of water or Bordeaux mixture will make a solution of 
sufficient strength to destroy cabbage worms and similar insects. It 
may, indeed, be used as strong as 1 pound to 10 gallons of water on 
hardy plants without injury, but this is inadvisable because of the 
increased cost, the danger of scorching young plants, and the fact 
that, thus used, it is no more effective than the prescribed dose. The 
paste form must be used at double strength, or 4 pounds to 50 gallons 
of water. The number of sprayings to be applied depends on local 
and seasonal conditions. Sometimes a single spraying at the proper 
time will suffice, but usually two or three applications are necessary 
for cabbage worms which have more than one generation. The 
adhesiveness of the spray material is promoted by the addition of 
about the same amount by weight of resin-fishoil soap as of the 
arsenical used. 
Arsenate of lead as a spray is valuable’in that it leaves, on 
drying, a white coating on the plants, so that after spraying it can be 
determined readily which plants have been treated and which have 
not been reached. 
Extensive experiments have proved that, for economy and effi- 
ciency, the best form of spraying machinery should be used. In 
regard to nozzles the “ Vermorel,” “ cyclone,” and “ mistry ” types are 
most effective as well as the most economical. When the arsenical is 
forced through a nozzle of this type the spray is mist-like in appear- 
ance and adheres to the foliage instead of forming small drops which 
quickly roll off the smooth leaves of cabbage plants. The best sprayer 
is the compressed-air type, constructed for use both by hand and by 
machinery, the latter to be driven by horsepower. 
POISONED-BRAN MASH. 
A mixture of bran with Paris green, the standard remedy for 
cutworms and grasshoppers, is, according to the testimony of some 
who have used it, successful against “ cabbage worms,” and should 
be tested against the imported cabbage worm. Any arsenical can be 
