A LIVING FROM THE LAND 



Plants that are underfed through inadequate 

 soil fertility or are weakened by other causes 

 suffer severely from insect attack, while vigorous 

 plants will come through with much less damage. 

 It is advisable to insure rapid germination of 

 seed through careful soil preparation, to seed 

 at the proper time for a quick and vigorous 

 start and to have sufficient available fertility 

 to stimulate growth once the plants have 

 started. 



There are two distinct classes of insects, the 

 division being based upon their feeding habits. 

 The larger group, both in the size of the insects 

 themselves and in the number of species, is 

 the leaf-chewing group. These can be destroyed 

 by the application of stomach poisons to the 

 plants under attack. The other group consists 

 of the sucking insects, which penetrate the veins 

 carrying nourishment to the leaves and appro- 

 priate it for themselves. Such insects multiply 

 with extreme rapidity, generally feed on the 

 underside of the leaves and may cause complete 

 wilting of the plant before their presence is 

 suspected. In such cases a "contact" spray or 

 dust must be used. This is based on the principle 

 of causing the insect to "inhale" the material 

 through breathing pores along its body. The 

 insecticide must be composed of extremely 

 fine particles or must be of such an oily nature 



106 



