ENTOMOLOGY 181 



roots. Many of the plants were putting out roots above the points of 

 injury, showing a strong recuperative tendency. 



In its earlier stages, also, the seed-corn maggot resembles the 

 house fly. The maggot is footless and cylindrical. It measures 

 about one-fourth inch in length. The color varies from nearly white 

 to pale yellowish. The maggot transforms into a puparium/ barrel- 

 shaped, and pale brown in color, measuring about 0.15 inch in 

 length. 



Owing to the difficulty of destroying root-maggots and other 

 subterranean pests and the cost of chemicals for the purpose, grow- 

 ers depend largely upon methods of prevention. To be thoroughly 

 effective these methods should be employed before the insect's eggs 

 are laid. 



For deterring the parent flies from depositing their eggs, place 

 sand soaked in kerosene a cupful to a bucket of dry sand at the 

 base of the plants, along the rows. This mixture will also kill young 

 maggots that might attempt to work through it. 



A carbolized form of kerosene emulsion is effective. This is pre- 

 pared by adding to 1 pound of soap boiled in 1 gallon of water, one- 

 half gallon of crude carbolic acid, and diluting the whole with from 

 30 to 50 parts of water. This mixture is applied about the stalks of 

 the plants affected. It is best to use it a day or two after the plants 

 are up, or are transplanted, and repeat every week or ten days until 

 the danger period is passed. 



Mineral fertilizers are useful as deterrents, particularly when 

 employed just before or after a shower has thoroughly wet the 

 ground. The principal fertilizers for this purpose are kainit, nitrate 

 of soda, and sulphate or chloride of potasn. They may be used as 

 top dressings before planting; or, if not employed until afterwards, 

 they should be applied as nearly as possible to the roots, the earth 

 being turned away from the plants for this purpose. These fertilizers 

 possess the advantage of acting also as a stimulant to plant growth, 

 thereby facilitating recuperation from root-maggot attack. 



Occasional Pests of Corn. The Oat Thrips (see Insects Affect- 

 ing Oats). The Fall Army Worm (see Insects Affecting Cotton). 

 The Corn Ear Worm (see The Cotton Boll Worm). The Army Worm 

 (see Insects Affecting Wheat). The Angumois Grain Moth, the 

 Little Grain Moth, the Indian Meal Moth (see Insects Affecting 

 Stored Products). White Grubs (see Insects Affecting Forage Crops). 



PRINCIPAL INSECT ENEMIES OF GROWING WHEAT. 



There are numerous insects, the number running into the hun- 

 dreds, which feed on and injure growing wheat. Most of these in- 

 sects are of rare or chance occurrence, and have no economic im- 

 portance whatever, although the fact that they are found on wheat 

 often leads the farmer to be curious about them or unnecessarily 

 arouses his fears. The great proportion of the losses to wheat fields 

 which is chargeable to insects is due to the attacks of less than half a 

 dozen species. These, in the order of their importance, are the chinch 

 bug, the Hessian fly, the wheat midge, and the grain plant louse. Of 

 second-rate importance are such insects as the wheat strawworm^, the 



