SELECTING MACHINERY AND EQUIPMENT 309 



(/) Consider Comparative Merits of Spraying and Dusting. 

 When materials are applied in water as a carrier, the operation 

 is termed spraying; when they are applied in the dry state, 

 with or without a carrier, the operation is termed dusting. 

 Spraying is the standard practice in most fruit sections at the 

 present time. In considering the purchase of machinery and 

 equipment for insect and disease control, however, the grower 

 will wish to take account of all the factors in the situation, 

 including both present practices and probable developments 

 in the immediate future. His investment in such machinery 

 and equipment cannot be repeated each season. It is impor- 

 tant, therefore, that he invest wisely, taking into account both 

 general facts and his own special conditions and problems. 

 Certain advantages in dusting are apparent. 



1. The work may be done much more rapidly. Dusting 10 acres 

 before breakfast or after supper is not at all out of the question. Thirty 

 acres of mature apple orchard and 40 acres of peaches may be dusted in 

 a 10-hour day with a modern outfit. This is nearly 5 times the average 

 that can be covered in the same period with an equally modem sprayer. 

 With a large acreage and a short period within which the application 

 can be made for the greatest effectiveness, with the period frequently cut 

 down by bad weather, and with the importance of reducing labor costs 

 to a minimum, this factor assumes great importance. 



2. The labor requirement is less. This relates both to the rapidity 

 with which the work may be done and to the number of men required 

 to do it. A large dusting outfit may be operated with one-third less 

 man power than a large sprayer. 



3. The water requirement is eliminated. No time is lost in hauling 

 water or in filling the tank. Sufficient materials for a half-day's work 

 may be carried on the machine, and supplies for the entire day may be 

 quickly distributed at convenient points throughout the orchard. 



4. The equipment is light. It may be used where the heavy liquid 

 outfit cannot be taken, on soft ground and rough land. As a rule, a 

 loaded duster weighs less than an empty sprayer. 



5. Dust may be applied when the fruit and foliage are damp, whereas 

 for spraying they should be dry. Time is thus saved in the morning 

 while the dew is on, or at night after it has fallen, or between showers. 



6. Standard dusting materials are less caustic and hence less likely 

 to cause burning than standard spraying materials. This is of impor- 



