THE BLACKHEAD FIREWOEM OF CRANBERRY, 31 



On the Howe vines in plat A, three applications, at an average rate 

 of 391 gallons per acre, with the mist nozzle produced a gain in yield 

 of 18.52 bushels per acre over the check ; 89.35 per cent of the berries 

 picked from sample areas were free from fireworm injury. On the 

 other hand, the same type of nozzle used on McFarlin vines in plat 

 H. with four applications at the rate of 485 gallons per acre, produced 

 a gain over the untreated vines in this section of 349.23 bushels per 

 acre, 93.81 per cent of the berries examined being free from fireworm 

 injury. 



Fig. 13. — Mist nozzle equipment used in spraj'ing experimental plats. 

 The Spray Gun. 



The spray gun (fig. 14) comprises usually a very large nozzle of 

 the eddy-chamber type attached to a piece of tubing of varying length, 

 fitted with a device for regulating at will the size and volume of the 

 spray delivered through the nozzle. It is of larger capacity than the 

 ordinary mist nozzle of the eddy-chamber type and is intended to be 

 used only on power outfits where the pressure can be maintained at 

 200 pounds or over. In these experiments this type of nozzle was used 

 at full-capacity opening with a medium-sized disk and threw a stream 

 of sj)ray about 15 to 20 feet long, which broke up into a medium fine 

 mist before it reached the vines. 



In the use of the spray gun on plats C, D, E, and F an effort was 

 made to fill the tips of the uprights with the spray liquid and also to 

 hit the undersides of the leaves by holding the nozzle close enough to 

 the vines so that the liquid would be delivered on a nearly horizontal 



