CONTROL OF CITRUS THRIPS IN CALIFORNIA AND ARIZONA. 11 
for spraying seed-bed and nursery stock, and they may also be used 
in young orchards of small acreage. 
The spraying outfit should be on hand, set up, and in perfect 
running condition not later than April 1, and the insecticide materials 
at hand and conveniently located near the water supply, and as 
close as possible to the orchard or nursery to be sprayed. It is neces- 
sary to order supplies not later than the January or February pre- 
ceding the spraying operations in order to insure having the material 
at hand when wanted. 
HOW TO SPRAY BEARING ORCHARDS. 
It is best to use only two 50-foot leads of hose on a power outfit, with 
10-foot rods each fitted witha‘ Y”’ (fig. 5) which is angled to handle two 
nozzles. The latter should be of the large chamber type, with disks 
bored to one-sixteenth 
inch, and should throw a 
double cone of spray which 
breaks into a fine mist at 
about 4 feet (fig. 6). The 
first application should 
usually be started just be- 
fore all the petals are down. 
While the sprayer is being 
driven between the rows 
each rodman should begin 
work at about the middle 
of his tree on the side 
away from the sprayer 
and work around the tree 
until he meets thestarting 
point; he should then 
switch to the same point 
on the next tree without 
shutting off the nozzles 
and with asmuch economy 
of movement as possible. 
(See figure 7, which shows 
easy and correct position 
for spraying.) 
The nozzles should be 
held about 2 feet from the 
tree so that the broad portion of the stream plays upon fruit and 
leaves. The trees should be swept from tip to base, special attention 
being given to the fruit and the tender growth, where the insects 
congregate. The pressure, if maintained at 150 pounds or more, 
will turn the leaves over so that both sides will be sprayed. No 
Pia. 6.—Mist spray from twin nozzles. (Original.) 
