230 Minnesota Plant Diseases. 



tention to this subject together with a few illustra- 

 tions of common types of apparatus now in use will 

 sufifice. They are intended merely for suggestions 

 which will lead to more careful study of the subject 

 by those seriously interested in this matter and as a 

 general description of modern methods of applying 

 fungicides. 



There are in general three kinds of pumps in com- 

 mon use. Bucket pumps are made for use with small 

 amounts of the fluid in ordinary buckets. They are 

 intended for small garden use and around the house 

 but are not convenient for extensive sprayings. 

 Knapsack pumps are suited for more extensive work 

 Fig. na. A and are used for low shrubs or potatoes or such crops 



convenient . . _. 



nozzle tor not casiIy accessible to barrel-pump apparatus, ihe 



spraying ^ „ . , , 



s'lde o^f '^'^^psack apparatus usually carries about three to 

 (DemlngCo.)^^^ gallous of fluid and is strapped on the back of 

 >the operator in knapsack fashion. Each is furnished 

 with a small pump and the operator works both the 

 pump and the spray. 



The barrel pumps are larger pumps intended for 

 attachment to barrels and should be strong enough 

 for spraying even fair-sized trees. They possess more 

 general usefulness than either the knapsack or bucket 

 pumps on account of the greater amount of fluid 

 carried and the capacity for work. The barrel is 

 best mounted on a farm wagon or truck and for or- 

 chards a platform for the operator is of great as- 

 sistance. The following have been given by Mr. H. 

 O. Gould of the Maryland Experiment Station as 

 the points of greatest importance in a good pump. 



"(i) The air-chamber should be sufficiently large 

 to ensure a steady spray and be so placed on the 

 pump that the latter will not be rendered top heavy 

 •thereby, or unduly cumbersome. 

 - Nozzle for (2) Somc meaus of keeping spraying mixture 



spraying , ,, . , . . f , . . 



plants in thoroughly stirred is essential, but it is not necessary 

 (Goulds Mfg. that this, be attached to the pump. 



4 



