28 BULLETIN 1032, U. S. DEPARTMEISTT OF AGRICL'LTURE. 



Plats A and B constituted one section, containing about an acre 

 of vines, C and D another to the south, and E, F, G, and H a third 

 to the east of C and D. Since the infestation of these three sections 

 varied somewhat it was thought advisable to have a check plat meas- 

 uring 1 by 2 rods for each section. As noted in Table 4. they were 

 placed to leeward of the plats of which they acted as checks to pre- 

 vent the unnatural spread of moths over the plats. These were num- 

 bered 1, 2, and 3, respectively. 



The percentages of berries free from fireworm injury, as shown in 

 Table 4, were obtained from an examination of the berries picked at 

 harvest time from five circular areas of approximately 100 square 

 inches each, selected at random on each sprayed plat. Berries were 

 examined from three such areas on each of the check plats. 



The yield of each plat was obtained by measuring its entire crop 

 as picked at harvest time. Plats A, B, C, and D were picked with a 

 scoop, and plats E, F, G, and H were picked by hand. The first four 

 plats included vines of the Howe variety and the last four, vines of 

 the McFarlin variety, all of which had reached the age of normal 

 bearing. 



Time and Nxtmbeir of Applications. 



The first three applications were made at practically the same time 

 for ail plats, since the growth of the two varieties on these plats w^as 

 very much the same. The first application was made on May 2 to 6, 

 about the time when the largest number of buds were pushing forth 

 but had not exceeded a growth of approximately three-fourths of an 

 inch. This was the time when the young larvae were appearing in 

 very large numbers but before manj^ of them had got bej^ond reach of 

 the spray. 



The second application was made May 20 and 21, when many blos- 

 soms were in the hook stage, and was timed so as to catch the next lot 

 of larvae before they could conceal themselves in the new growth. 



The third came June 13 to 17, when the vines were nearly in full 

 bloom. It was designed to kill any late-hatching larvae of the first 

 generation which might have been injuring the blossoms and newly 

 forming berries. 



Plats C, E, G, and H received a fourth application on July 9 and 

 10 at about the time many berries were already set. This applica- 

 tion was intended to kill any very late-hatching larvae and the moths 

 which appeared on the bogs in largest numbers about this time. 



The Bordeaux Nozzle. 



The Bordeaux nozzle is modeled so as to deliver a forceful, driving 

 spray in the shape of a fan. The nozzle is so arranged that the in- 

 tensity of the fan-shaped spray can be regidated as desired. In 



