78 



INSECTICIDES AND SPRA\ING. 



wood, costing under two rupees to prepare. It covers very little ground, 

 however, and is suitable only for gardens and small holdings. It is 

 especially useful for applying contact poisons to small colonies of plant 

 lice, mealy bugs and other sucking insects. With it one can rapidly and 

 effectively kill such insects when they are few. It is not adapted to larger 

 areas, but as a check on incipient diseases it is invaluable and admirably 

 suited to the ryot. If this were in general use, the plant lice that ravage 

 cotton, wheat, mustard and other staple crops could be nipped at the 

 start and never get a real hold on the crop. 



For more extensive spraying, a larger machine must be employed, 

 and the Success Knapsack Machine l is a useful pattern obtainable in 

 India at a cost of E/s. 46. This machine holds four gallons of insecticide 

 and can be worked on the ground for spraying fruit trees or on the 

 back for spraying crops. The insecticide is pumped through the rubber 

 hose out at the nozzle which breaks it up into a fine mist. Either 



of two nozzles can be used, 

 and of the two the Bordeaux 

 has the most general application 

 and value. The machine is built 

 of copper and brass, which are 

 not destroyed by insecticides. It 

 requires to be kept clean and 

 will last for years with the 

 occasional renewal of the rubber 

 tube. With this machine from 

 one to two acres of crop can be 

 sprayed in one day, using two 

 men at the machine and others 

 to bring water, mix insecticides, 

 etc. This refers to cases where 

 continuous spraying is required 

 as when a whole crop is to be 

 sprayed with lead arseniate. 

 Where individual plants here and 

 there are to be sprayed, as when 

 aphis is attacking cotton, a far 

 larger area can be covered daily. 

 Larger machines are used to apply insecticides to fruit trees, to special crops 

 and, in Europe and America, to field crops. It is unnecessary to discuss 

 these at present as they are not likely to be used for field crops in India, 

 1 English copies of descriptive leaflet are available, 



FIG. 95. 

 Success Knapsack Sprayer. 



