INSECT PESTS OF OHIO SHADE AND FOREST TREES 191 



A supplementary nozzle is sometimes employed to break up 

 the solid stream into a fine spray at the nozzle tip in order to enable 

 one to spray low trees and shrubs or the lower branches of high 

 trees with the solid-stream outfit. The working principle of this 

 nozzle is a sharp pin which centers in the solid stream or a deflect- 

 ing flange at the sides. (See Plate XIV, Fig. 2.) 



The soHd-stream machines are used almost exclusively at pres- 

 ent in the eastern and New England states, where they have been 

 developed to meet the requirements of a machine for spraying large 

 trees in a rapid, economical manner in connection with the sup- 

 pression of the gipsy and brown-tail moths. Two are owned and 

 operated in Ohio today, the village of Bratenahl, adjoining Cleve- 

 land, having secured a machine 2 years ago for use in eradicating 

 a very small colony of gipsy moth which had been introduced, and 

 more recently the city of Cleveland purchased one for general street 

 and park use. 



However, it is the writer's opinion that the machines of this 

 type will in time come into general usage for street and park work 

 throughout the Union, where such work is done, since they have 

 demonstrated beyond question their superiority over the mist types 

 for this purpose. 



Operating a solid-stream sprayer. — The effectiveness and 

 economy of the solid-stream machines depend largely upon the 

 manner in which they are operated. Because of the tremendous 

 volumes which these machines deliver, it is easy for untrained or 

 careless operators not only to waste the spraying material but to do 

 imperfect spraying as well. The force required depends, of course, 

 upon the character of the work which is being done, but in street 

 work, six to eight workmen should accompany each outfit. One 

 man should drive the team and another remain in constant attend- 

 ance of the apparatus. A third man should manipulate the nozzle, 

 and between the nozzle man and engineer the closest harmony 

 should exist, in order that they may work together. When the 

 nozzleman for any cause is forced to shut off the nozzle, the engi- 

 neer should immediately slow down the engine and when the nozzle 

 is opened the engineer should instantly respond with full speed. 

 If the engine is not slowed down, and the overflow valve fails to 

 work properly, the hose is certain to give way ; and if full power is 

 not given immediately when the nozzle is opened, much mixture is 

 lost before the pressure mounts to the proper point to give a first- 

 class solid-stream spray. The people of Bratenahl found it advis- 

 able to send to New England for an experienced engineer and nozzle- 



