Spray Calendar. 63 



stiff. It is necessary to have the hands well greased with tallow 

 while handling this wax. — From the Yearbook of the United States 

 Department of Agriculture. 



INSECTS 



Prof. Willis G. Johnson says: "At the present time, spraying 

 is an important part of successful fruit-growing. The regular and 

 systematic application of insecticides and fungicides is one of the 

 most valuable and profitable pieces of Avork done on the farm. The 

 spray pump, properly used, is worth as much to the grower of 

 fruits and vegetables as the policy covering the insurance on his 

 house or barn. In fact, you must 'insure' your crops from destruc- 

 tive insects and fungi by practicing modern methods of spraying. 

 There has been a decided awakening to the truthfulness of the above 

 statement in the past few years, and thousands of growers are now 

 spraying and seeking information, where only a short time ago they 

 Avere counted by hundreds." 



In order that our readers may understand why one remedy is 

 used for one insect and not for another, it will be necessary for us 

 to make some brief references to the structure and habits of cer- 

 tain types. For example, the great mass of injury to plants by in- 

 sects falls under two heads : First, where the plant itself has been 

 eaten; and, second, where the juices have been sucked out, leaving 

 the tissues. 



Biting insects— Insects causing injury of the first class are called 

 biting or chewing insects, familiar examples of which are the 

 beetles, grasshoppers, and caterpillars, such as the cabbage worm, 

 anny worm, etc. They have well-developed jaws, fitted for cutting 

 and chewing the plant. Such insects can be destroyed by use of di- 

 rect poisons, such as the arsenicals. When applied to the leaves or 

 other parts of the plant, it is eaten by the insect, causing its death. 



Sucking insects— On the, other hand, the second type have long 

 lance-like beaks, fitted for sucking. This class includes the scale in- 

 sects, plant lice, squash bug, harlequin, or terrapin bug, etc. They 

 obtain their food simply by inserting their beaks into the tissues 

 of the plants, sucking the juices from within. The external appli- 

 cation of arsenical poisons to plants would have little, if any, effect 

 upon this group of insects, as the poisons do not enter into the cells 

 of the plants. It is necessary, therefore, to employ some other sub- 



