BEOOMM KN DATTONS. 
89 
Carbonic-acid-gas sprayers. — Carbonic aeid is employed as power in a .similar manner 
to compressed air. It is, however, somewhat more expensive than either horsepower 
engines, gasoline engines, or compressed air. More or less difficulty sometimes occurs 
in procuring the drums of gas, which have to be obtained from large cities where this 
gas is manufactured. Yet there are many of these outfits in use and giving good 
satisfaction. 
Hand pumps. — Where but limited areas of vineyard are to be treated quite effect- 
ive work may be done with a pump operated by hand to treat vines, and in gardens 
or places where it is impossible to drive a cart a knapsack sprayer may be used. For 
larger areas, however, it will be found more economical to use power outfits. 
The care of spraying apparatus. — For the successful operation of spray pumps it is 
highly desirable that the working parts be made of brass, since iron is acted upon 
by Bordeaux mixture. It is also important that the pump be so constructed that 
packing can be conveniently removed and replaced. Each time after the pump is 
used a few pailfuls of water should be run through the pump, hose, and nozzles to 
remove all of the spray mixture so that sediment in the mixture may not dry up and 
clog the valves and nozzles while the machine is not in use. If this precaution is 
taken much annoyance may be avoided when the machine is next put in operation. 
Nozzle adjustment. — Practically all of the power sprayers are equipped with adjust- 
able nozzles attached to a vertical rod firmly fastened to the sides of the tank, usually 
at the rear end of the machine. There are usually two or three of these nozzles set 
horizontally to throw the spray into the side of the vines. In addition to these hori- 
zontally directed nozzles, the uppermost nozzle 
should be carried out over the top of the trellis and 
directed downward to insure the covering of all the 
foliage on the top of the trellis (PI. X, figs. 2, 3), 
since it is upon the new growth developing at the top 
of the trellis that the beetles are likely to do much 
feeding, especially after the lower foliage has been 
thoroughly covered with a spray mixture. 
Nozzles. — Nozzles of the Vermorel type are the 
kind in general use for vineyard spraying and pro- 
duce a fine mistlike spray which is so necessary for FlG - 31.-A large nozzle of the cy- 
effective work, and for this reason they are more 
desirable than nozzles of the Bordeaux type, which throw a heavier, fan-shaped 
spray. The chief drawback with the ordinary Vermorel nozzles lies in the rapid 
wearing out and enlarging of the opening of the cap, resulting in a coarse spray if 
allowed to become too much worn. More recently larger nozzles of the Cyclone type 
(fig. 31) have come into general use, especially where high pressure with power 
machinery is used. These nozzles throw a larger cone of spray, have steel disks for 
caps, which can be removed when the opening becomes much worn, and possess 
the added advantage of not clogging so readily as the smaller Vermorel nozzles. 
RECOMMENDATIONS. 
DESTRUCTION OF THE ADULTS OR BEETLES. 
The beetles of the grape root-worm feed upon the upper surface 
of the leaves of the grapevine, and may he poisoned by thoroughlv 
spraying the foliage of the vines with an arsenical. The first poison- 
spray application should be made as soon as the fust beetles are 
found upon the vines. Our observations indicate that the beetles 
feed much more freely immediately alter emergence from the soil 
