36 FROGHOPPER BLIGHT OF SUGAR-CAXK. 



The infestation appears to have been greatest at Caroni. Gilbert 

 (1908) siys that it first appeared in early August in 1st ratoons. 

 Between ii5th and 29th August 600 acres were affected. It cleared up 

 slightly at the end of September and then returned worse than ever. 



Carmody (1909 B. p. Ill) commenting on the above attack says "the 

 virulence and concentration within a limited area of the froghopper 

 attack at Caroui were as surprising as the unexpected abundance of the 

 larvae of Castnia, and strongly indicate the real cause of the attack." 



1909. 



There was a considerable reduction in the froghopper infestation this 

 year and little damage appears to have been done. In spite of this the 

 crop was slightly below that of the previous years. In this year Mr. 

 Urich was appointed by the Board of Agriculture to investigate the pest. 



The first brood of adults was very early and bj' the 22nd of June 

 there was a blighted field at Woodford Lodge, and on July 2nd, there 

 W'Cre trace? of blight at Caroni. (Ui'ich 1910 A. p. 19). 



The second brood appears to have been at its height about 18th to 

 16th August and a few fields at Caroni were slightly blighted in 

 September. 



The third brood appeared in October and on 6th October at Caroni 

 28,875 adults were caught in 13 lamps (Urich 1910 A. p. 20). Canes were 

 blighted at Orange Grove, Caroni and Woodfoi'd Lodge, but Waterloo 

 reported that "Froghopper has been general, but not to the extent of 

 producing blight, although it certainly retarded growth." 



Urich reports adults fairly numerous in canes and grasses at Wood- 

 ford Lodge on loth January, so that a fourth brood seems to have 

 occurred in this locality. 



1910. 



This year also was comparatively free from blight, particularly in the 

 Couva district, but there is again a considerable drop in the total sugar 

 crop, which is 5,000 tons belbw that of 1909-10. 



The particulars below are mostly from Urich's monthly reports to the 

 Board of Agriculture. 



Slight blight appeared at Woodford Lodge in August, in two small 

 fields in October, and in November and December in ratoon canes at 

 Caroni and Woodford Lodge. Froghoppers were caught by thousands 

 in light traps in December at Woodford Lodge, and continued on into 

 January but "only in hundreds" where there had been thousands before. 

 (Urich's report for February 1911.) 



From this it seems probable that the three broods were at the end 

 of July, the end of September, and the end of November, but this does 

 not correspond with the diagram given by Urich (19 1 3 C Plate VIII) of 

 captures by six light traps at Woodford Lodge. This shows two periods 

 of greatest abundance in September and January but does not corres- 

 pond to his written reports. It may be that the light traps were out 

 more frequently in some months than others. 



The dry season of this year was unusually wet and this may have 

 causeJ the broods to be more confused. 



1911. 



There was a marked inci'ease of blight in this year, chiefly in tlie 

 Couva district, and, as a result of the prolongation of the dry season, 

 the broods were considerably later than in 1910. According to Guppy 

 (Rejiort to the Board of Agriculture November 1911) there were three 



