43 6 MAIZE 



CHAP, corn bill-bugs, and the chinch-bug, none of which occur 

 in South Africa. 



The insect pests of maize appear to multiply in greater 

 numbers as the acreage under crop is increased. Some 

 farmers, accustomed to the easy production of good crops of 

 maize before maize pests were as troublesome as they now are, 

 have been inclined to abandon the crop in favour of some- 

 thing else which they hope may be produced more easily. 

 Speaking generally, the man who cultivates his land well and 

 at the proper time, and who adopts ordinary methods of 

 precaution, is not seriously troubled by insect pests, and this 

 fact should be borne in mind by those who are inclined to be 

 discouraged. 



The most troublesome pests of the maize plant in South 

 Africa are: (i) the cutworms, larvae of several species of 

 moth (Agrotis) ; (2) the stalk-borer, top-grub, or tassel-worm, 

 the larva of the moth Sesamia fusca Hampson ; (3) the striped 

 beard-grub or ear-worm, the larva of the moth Heliothis armi- 

 ger Hubn. ; (4) the maize cricket, which feeds on the young 

 silks ; (5) locusts (Acrididm) ; and (6) the tok-tokje {Psam- 

 modes Reicliei S.). All of these attack the growing plant. 



401. Methods of Combating Insect Pests of the Maize Crop. 

 — The maize crop appears to suffer most from insect attack 

 either when it is grown on newly broken veld, which has for 

 a long period lain in grass or weeds, or when it has been grown 

 on the same land for several years in succession and has there- 

 lore become weedy. 



Some of the weeds of the veld and of maize fields are the 

 partial host-plants of certain insects which also live upon the 

 maize plant. These weeds therefore serve to carry over 

 the pest from one crop of maize to another. By preventing 

 the growth of the weeds we interfere with the life-cycle of the 

 insect ; hence the most effective preventives against such insect 

 attack are short and systematic rotation of crops, together with 

 clean culture of the maize fields and of the surrounding land. 



Where the land is neither in grass nor maize for more than 

 two years in succession, the attacks of insects are comparatively 

 limited, except perhaps in the case of certain migratory ones 

 such as locusts, whose increase in numbers has been brought 

 about by special conditions. 



