1912.] PUBLIC DOCUMENT — No. 31. 57 



W. Pettigrew, superintonck'nt of the Boston park system, was 

 one of the first to construct a really effective spraying equip- 

 ment provided with high-pressure gasoline engines and modern 

 coarse spray nozzles. This was used with much satisfaction 

 some years ago in spraying woodlands for the gypsy moth and 

 for park work, and on this model were constructed the later 

 and more improved types of machines. In 1896 he employed 

 a more or less cumbersome outfit for spraying in the public 

 parks of Brooklyn, N. Y., consisting of an ordinary road 

 sprinkler and a 10-horse power portable steam boiler fitted 

 to a large pump. He made use of a %-inch hose provided 

 with /iG or 1/4 inch nozzle. 



About the same time l\h\ Christopher Clark, the veteran 

 city forester of Northampton, Mass., made use of a similar 

 machine for spraying elm trees. Mr. Clark's equipment con- 

 sisted of a small steam boiler which used coal for fuel, and a 

 Duplex jnunp mounted on a truck. The j)ressure he ol)tained 

 from this equipment was something over 100 pounds. lie used 

 an ordinary garden hose nozzle of l/g-inch aperture and obtained 

 a coarse spray, not in any way comparable, however, with 

 that obtained from the use of modern equipment. Other make- 

 shifts, which used steam for power, were employed here and 

 there about the same time, but these were all crude affairs 

 compared with the modern outfit. 



Those who have had opportunity to make extensive compari- 

 sons of the high-pressure, coarse-nozzle spraying and the fine 

 mist spray tinder low pressure are generally convinced that, 

 considering the cost ,and eflSciency, the former method is far 

 superior to the latter for certain work. The question there- 

 fore arises to-day whether or not high-pressure coarse-nozzle 

 spraying cannot be applied to orchards v/itli the same results 

 that have followed its use in other ways. Recent experiments 

 made in Virginia ^ have shown that for the control of the 

 codling moth the high-pressure, coarse-nozzle spray has proved 

 superior to the low-pressure mist spray. The best high-power 

 sprayers in use at the present time have reached a high degree 

 of perfection, especially the machines manufactured for and 



» Spraying for the Codlin? Moth, West Vir. Agr. Exp. Sta., Bui. No. 127. 



