34 TirR RICE WORM (TYf.ENCHUS ANGUSTUs) AND ITS CONTROL 



In the following year the bund was maintained and the experiment was super- 

 vised by the Agricultural Department. Sowing was done at the right time 

 and a good crop, free from ufra, was obtained. 



In the other area the bils selected were at a very low level and had suffered 

 very severely from ufra for several years. The stubble was reported to have 

 been burned in December, 1915, a^id the land ploughed early. The writer, 

 however, examined the conditions in December, 1916, and concluded that it 

 would be quite impossible to burn the stubble effectively in these particular 

 bils so soon after harvest. In December most of the fields reported to have 

 been burned were found to be still too swampy in the lower levels to enter, 

 and even on February 28th, 1917, the central parts were still damp and soft. It 

 would have been quite impossible with the means at the disposal of the workers 

 to have gathered together and burned much of the stubble in the swampy parts 

 before February, and even then a good deal would probably get pressed into the 

 mud by the bullocks used for collecting it and for the subsequent ploughing. 

 A very severe attack of ufra occurred in the treated fields, some of which gave 

 practically no crop when harvested in November-December, 1916. In this 

 case the treatment had not done the slightest good, but under the circumstances 

 more could not have been expected. In 1917 the experiment was repeated 

 under the supervision of the Agricultural Department, care being taken to 

 postpone burning until the fields were dry enough to render it effective, which 

 was not until February 21st. Two fieMs were treated and in both there were 

 signs of ufra early in September. In one field about one-eighth of the crop 

 was ultimately lost, in the other about one-fourth. For the first time for a 

 number of years a paying harvest was obtained. 



This last case introduces the main difficulty that is likely to be encountered 

 in carrying out effective treatment of ufra. Throughout certain parts of the 

 diseased tract low-lying patches of varying size are encountered in the middle 

 of the paddy bils, which remain swampy well into January. In a'l of these 

 which have had deep-water aman the stubble is left and usually gives a growth 

 of small shoots and ears from December on until the ground dries, which may 

 not be till late February. This only allows at most a month before the new 

 crop is sown, as these low patches are always sown early, and not three months 

 before the humidity rises enough to permit free infection. The second growth 

 is liable to infection up to January in Dacca and into February in Noakhali. 

 Before the ground is covered with water the worms have had only a short 

 period in the dormant condition. They are then set free into the water in 

 large numbers. Two months later the humidity is certainly high enough to 

 permit migration and it is not unlikely that in these hollows, where the crop 



