194 
TREES AS GOOD CITIZENS 
will be thrown into spray as it reaches their tops and will 
then descend as a mist over the tree. 
For the most extensive spraying operations motor 
truck sprayers are sometimes used. 
Accessories for Spraying. —There are many types of 
spraying nozzles, but the one which has been found 
most generally efficient, for both medium and small 
outfits, is the whirlpool disc type, adjustable to fine, med¬ 
ium or coarse spray. This nozzle is compact and does 
not catch in branches or twigs. 
For reaching the upper and inner parts of a tree, where 
a mist spray is used, an extension rod is useful. This is a 
rod of aluminum, iron or brass, fitted into a bamboo pole, 
made in lengths of from 6 to 14 feet, and is used for hold¬ 
ing the nozzle above the head of the operator. 
A combination of nozzle and extension rod is the 
Worthley nozzle, several feet in length, which directs a 
solid stream and makes it possible to reach the top of an 
85 foot tree while the operator is standing on the ground. 
For foliage nearer the ground and for small trees the 
nozzle has a spreader which breaks the force of the solid 
stream and produces a fan-shaped spray. 
For the larger power outfits and heavier work a nozzle 
like that used on a fire hose, but of smaller size, is best. 
The hose used in spraying should be of the best grade, 
made for high pressure and from % to % inch inside 
diameter. 
In the absence of spraying equipment, a common 
paint or whitewash brush may be used to good advantage 
in applying treatment to the trunk and larger branches 
of a single tree, or even a small number of trees. This 
method is used against the scale insects, and the spray 
material is spread on the bark with the brush. Even the 
caustic lime-sulphur may be thus applied if proper pre- 
