188 OHIO .EXPERIMENT STATION: BULLETIN 332 



Hose. The best grade of spray hose obtainable should be used and is 

 most satisfactory if divided into 100-foot lengths. Three hundred feet is ade- 

 quate for street work, but where park spraying is done, especially if the land 

 is very uneven, 500 or 600 feet should be provided. If no more than 300 feet 

 is in use, the hose may be of the half -inch size, but where greater lengths are 

 employed, at least the first 200 feet, that is, the section nearest the machine, 

 should be three-fourths to 1 inch and the remainder may be of the smaller 

 caliber. Under some conditions it is possible to run two lines of hose to 

 advantage, but as a usual thing, particularly in street work, one line is found 

 to be best, two or more large capacity nozzles being employed to expedite the 

 work. Particular care should be given the type of hose connections used, since 

 the dragging about of the long lines subjects the hose to a tremendous strain, 

 and unless the connections between the sections are especially well constructed 

 they are pulled out. Supplementary sections of hose should be carried with 

 the machine so that in case a section breaks in use, or the connections pull out, 

 another unit may be supplied and the defective one repaired at leisure. 



Extension rods. Brass-lined, bamboo extension rods, 10 to 12 feet in length 

 and equipped with drip guard and leakless cut-off should be used. At least 

 one and preferably two extra rods should be carried with the machine. 



Nozzles. Nozzles of the large disc type, at least two to the extension pole 

 and set at an angle of about 30 are best. Several extra nozzles should be 

 carried. 



Tool box. While seemingly a minor item, a spacious tool box, well filled 

 with tools and extra supplies, is especially desirable in city spraying. Not 

 infrequently the machine is used several miles from its base of operation and 

 in the absence of a generous set of tools, a repair of insignificant importance 

 may delay the work several hours while a trip is being made for the necessary 

 implements or supplies. 



Truck. The truck should be well constructed; equipped with wooden 

 wheels, high-grade springs and a brake. These three specifications are each 

 of especially great importance. Iron or steel wheels rarely will survive the 

 unevenness of the average city pavement. Wide-tired, heavily constructed 

 wooden wheels with many spokes, seem the only type that will give satisfaction. 

 The springs are necessary since without them long hauls over rough pavement 

 usually jar loose some part of the machine and may thus cause no end of incon- 

 venience and delay. 



The loaded city sprayer usually weighs from 3 to 4 tons; thus a brake is 

 essential to the safety of operation. 



The final specification concerning the truck is that it should be of the cut- 

 under type to facilitate turning. Attention is called to Plate VIII, Fig. 1, 

 which shows a well-constructed and equipped sprayer of the mist type. The 

 machine illustrated is owned and used by the Board of Park Commissioners of 

 the city of Cincinnati. 



Operating a municipal mist sprayer. During the period of 

 about 10 years that the writer has spent in the study of the shade 

 and forest insect problem in Ohio, he has had the opportunity of 

 observing and of doing a considerable amount of actual spraying 

 under city conditions. From this experience he has learned that 

 operating a sprayer in the city and in the country are two entirely 

 different affairs. For instance, and especially in street work, no 

 matter what the capacity of the machine, more than one line of 

 hose can rarely be used. The constant passing of vehicles makes 

 it impracticable to operate upon both sides of the street at once, 

 and if two men try to spray on the same side, they are constantly 

 interfering with one another. In order to facilitate the work, there- 



