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thought to have been more plentiful than in any other season since 

 the present locust cycle began five years ago. 



The damage done to standing crops by the locusts is considered 

 to have been slight, A few fields of wheat and other cereals were 

 destroyed, but these were exceptional cases. A far more important 

 loss w as that of stock becoming poisoned. The farm value of animals 

 alleged to have been fatally poisoned is estimated at about £3,300, 

 and further loss was incurred through animals being made seriously 

 ill for a time. While in theory no loss of stock should occur in this 

 connection if simple precautions are taken, in practice an occasional 

 loss through accident or mischance must be expected, and such loss 

 must be regarded as part of the cost of fighting the locust invasions. 

 At present the Government assumes no responsibility whatever for 

 any losses, but in view of the gravity of the loss in the season under 

 review, the author has recommended that sufferers should receive 

 some compensation. The importance of poisoning the locusts early 

 in their existence, when the risk to stock is trifling, is pointed out, 

 and also the necessity for safe disposal of empty poison drums. The 

 South African Agricultural Union in January adopted a resolution 

 that the present locust law was considered to work unfairly and to 

 place a heavy burden on a section of the farming community where 

 the outbreak first occurred, that section having to bear the brunt 

 of work and expenditure connected with locust extermination, and 

 urged the Government to provide labour, under an inspector, to assist 

 in the destraction of locusts. The author however, considers that 

 it would be a mistake to remove the responsibility from the occupier 

 or to provide labour until he has reached the limits of his own resources, 

 but he acknowledges that the burden on the occupier of pastoral 

 farms is too heavy and suggests further assistance after losses have 

 occurred and further Government measures to secure the destruction 

 of swarms to the fullest extent practicable by the occupier of the 

 farms on which they first appear. The total Government expenditure 

 for the season's operations was approximately £15,000, while the total 

 cost to the country is reckoned at about £27,000. 



Special investigations were carried out on insects injurious to the 

 wattle, which is widely cultivated in Natal for tan bark. It was 

 proved that the chief pest, the bagworm [Chalioides junodi], is con- 

 trollable by dusting the infested trees with powdered arsenical insecti- 

 cides diluted with finely powdered lime. This is a troublesome remedy, 

 but in view of the lack of natural parasites or of the prospect of increas- 

 ing the efficiency of those that are present, or of introducing better 

 ones, the practice of dusting should be developed. Continued attention 

 has been given to the problem of combating the maize stalk borer 

 {Busseoh, fusca, Hmps.). Other insects dealt with during the year 

 include pea and bean weevils. Winter sprajnng against Pseudococcinella 

 sexvitiata (olive leaf beetle) resulted in the trees being practically 

 free from the pest through the spring and summer. Blissus diplop- 

 terus (South African grain bug) caused considerable loss of wheat, 

 oats and barley in some districts. There is only one generation in 

 a year ; the mature insects shelter in the bark of trees, in cracks in 

 fencing posts, dry maize stalks, etc. from midsummer onwards, and 

 in winter migrate to the grain fields. In July and early August the 

 insects were on the wing in great abundance ; the plants are most 



