KEl'OK-r OK I-IIB ENTOMOLOGICAL SECTION 133 



cutworm has appeared on Nuri basin in previous seasons, increasing in nuinlici-s every 



year. Some four years ago the area of land iu this basin, available for cultivation, was 



considerably increased by the construction of a canal, and the occurrence of A. ypMon in 



noticeable numbers appears to date fi-oni then. In 1909, the barley and other crops 



were entirely destroyed when they were only a few inches in height and the land was 



then thoroughly hoed. Numbers of birds followed the men engaged in this work and B'r'i enemies 



devoured the larvte which were exposed, a bird known locally as yairdouu — a species 



of wagtail — being particularly beneficial iu this way. The crops were then resown and 



were not again attacked by cutworms. The basin was searched for cutworms in the 



latter end of May, 1910, and although there was a considerable area of land under crops 



watered by well-sakias, and the whole basin was more or less covered with terroba 



and other weeds, the only traces of the pest which could be found were empty pupal 



cases iu the soil. It is believed that the moths were in hiding in the deep cracks in 



the ground — these cracks may extend to two metres in depth — or in similar places. 



Preventive and remedial meamiret:. — In other countries ^1. ypsilon usually produces 

 several generations in the course of the year, but in Dongola Province it appears to be 

 single-brooded. Should it continue to be single-brooded in the future its control should 

 be effected by purely cultural methods, and even were it to acquire the habit of breeding 

 throughout the year it should never attain the importance, as a pest, of the dura stem- 

 borer — Seiiaima cretica — if measures are taken to keep it in check. The cultural methods 

 recommended are as follows. When the water soaks away or recedes from the basins, and 

 as soon as the land is sufficiently dry to permit of its being done, the soil should be 

 well hoed, or ploughed, and cleared of all weeds. This operation will enable birds to 

 devour numbers of the larvae, others will be crushed and the remainder will be hard put to it 

 to iiiul sufficient food to enable them to comjalete their life-cycles. This hoeing should also 

 yield good results in other ways — it will tend to conserve the supply of w-ater in the 

 soil by preventing undue evaporation, and the soil itself will be sweetened by the action 

 of the sun and air. If there is no second breed of cutworms, crops sown on land treated in Prevention of 

 this way will be safe from attack, but should a second brood appear it will be necessary to 'he Greasy 



^^ •' Cutworm 



have recourse to the use of poisoned baits or to hand-picking. This latter process is 

 somewhat costly and needs to be very thoroughly done to be effective, moreover sufficient 

 labour for the purpose may not be available, and consequently it cannot be recommended 

 except for small areas. The destruction of the larvae by means of poisoned baits has 

 been found in other countries — notably in the United States — to be the most practical and 

 efficient method of dealing with cutworms over large areas, the substances used as 

 baits including bran, meal, etc., and green forage. The latter has several advantages over 

 bran and meal, and is used in the following way. Any available green-stuff — e.g. herseem., 

 grass, barley, young succulent weeds, etc. — is collected, out up into small pieces of 

 about half-an-inch to an inch in length and moistened with a mixture made up of 1 lb. 

 arsenite of soda, 8 lb. treacle and 10 gallons water. This poisoned forage is then thinly 

 scattered over the infested land. This should be done a few days before the croij appears 

 above the ground and, if necessary, again if injury is noticed after the plants have begun to 

 grow. The land should be thoroughly cleared of weeds before the first application. 

 Cutworms will take green forage treated with this mixture in preference to untreated 

 growing plants, owing to their love for sweet things. By applying the poison in this way 

 there is very little danger of cattle, sheep, donkeys, etc., being poisoned, for the pieces 

 of green forage are too small to be readily picked up. Care should be taken, nevertheless, 

 that live-stock, including poultry, do not have access to land which has recently been 



