Corn leaves that are fully open are usually covered more thoroughly with spray than 

 rolled leaves because of lack of moisture. In any case, fungicides only provide 

 protection against new infections, and must kill the blight fungus before infections 

 occur. The fungicides will not kill the fungus growth that is already in the plants . 



Spray equipment and dosage . Both aerial and ground equipment should give equally 

 effective results when used properly, but aerial spraying has some advantages. There 

 is no mechanical damage to plants, no waiting to get into fields following heavy 

 rains, and greater speed. 



For aerial application, use 3 to 5 gallons of spray per acre. At the lower rate, it 

 is essential for the spray nozzles to be located properly on the boom and for air- 

 craft to fly at the optimum height and swath width. (See the table for spraying de- 

 tails.) 



If you use Dithane M-45, add Triton CS-7 spray adjuvant to the spray mix. If you 

 spray with Manzate 200, use DuPont Spreader-Sticker, Bio-Film, or some other sur- 

 factant suggested by the manufacturer. The addition of a compatible spray adjuvant 

 to the mix at the recommended rate will improve the distribution, spread, and re- 

 tention of the fungicide deposit. 



When using ground sprayers, three drop nozzles on each side of the row, spaced 12 

 to 18 inches apart, should be sufficient to protect the top five or six leaves and 

 the ears. Aim the bottom nozzle slightly upward. Cover the critical whorl area 

 with one or two nozzles over the row. Use the same spreader-stickers suggested 

 for aerial application. 



Spray Equipment and Dosage Suggestions for Application by Air or Ground Equipment 



Aerial application 



Ground application 



Rate. 



Sprav and 

 surfactant. 



Volume. . 

 Pressure. 



Nozzles . 



Droplet 



size. . 



(.Fixed wing or helicopter) 



1-1/2 lbs. of maneb and zinc ion per 

 acre for each spray 



Dithane M-45 --Triton CS-7 

 Manzata 200--IliPont Spreader- Sticker 

 Bio- Film, or other- -as recommended 

 by the manufacturer 



5 to 5 gallons of water per acre 



50 to 51) p. s. i. 



(a) Boom with hollow-cone nozzles 

 comparable to spraying systems 

 D-4 or D-b discs with No. 45 

 cores. Use 18 to 24 nozzles 

 for 5 gallons per acre. Use 

 50 to 44 nozzles for 5 gallons 

 per acre. 



(b| Micronair rotary atomizers 



Medium (200 to 400 nucronsj . Angle 

 nozzles back 15 degrees on aircraft. 

 Slow down micronairs. 



High clearance sp ravers) 



1-1/2 lbs. of maneb and zinc 

 per acre for each spray 



ion 



Dithane M-4S--Triton CS-7 

 Manzata 200- -DuPont Spreader-Sticke 

 Bio-Film, or other- -as recommended 

 by the manufacturer 



20 to 40 gallons of water per acre 



40 to 100 p.s.i. 



5 drop nozzles on each side of the 

 row :md 1 or 2 nozzles over the 

 whorl area. Use hollow-cone nozzle 

 comparable to Spraying Systems D-5 

 or D-4 discs with No. 25 cores. Use 

 slotted strainers equivalent to 25 

 mesh. 



Medium (200 to 400 microns). Avoic 

 fogging sprays. 



