Be 
Swath Width 
The swath width is chosen first by the locations in the crop through 
which the machine can be taken with the least damage from its wheels. 
The minimum swath width is limited by the particle size requirements. 
A narrow swath requires large particles to settle out in the swath. 
Large particles sometimes cause foliage injury when oil solutions are 
used. The maximum swath width is limited by the dosage requirements. 
A wide swath requires a heavy output from the machine. Too heavy an 
output, even though the particle size is small, will cause foliage 
injury due to the heavy deposit near the source. The smaller particles 
are less efficient in depositing within a limited area. For this reason 
it is best to select a swath as narrow as possible without causing too 
much damage from the wheels of the machine or foliage injury from the 
large particles. 
Particle Size 
The proper particle size depends on the swath width the aerosol is 
expected to cover, the wind velocity, and the amount of foliage penetra- 
tion required. 
After the swath width has been chosen, the particle size that will 
give 25 to 50 percent deposition of the aerosol at different velocities 
may be obtained from table 2. These values were computed for an aerosol 
cloud released at an average height of 10 feet and under good inversion 
conditions. If penetration of dense foliage is required, the particle 
Size indicated should be reduced by one-half. 
Table 2.--Optimum particle size, in microns mass median diameter, of aero- 
sols applied at different swath widths and wind velocities 





; Wind velocity in miles per hour 
Swath width (feet) 
50 oy) 98 = = 
100 40 70 92 -~ 
200 29 50 65 till 
250 26 45 60 70 
300 2h 40 53 63 
400 21 35 46 oy) 
500 18 Bp) 41 49 
aly/ Application at higher wind velocity is not recommended. 
