DIAMOND-BACK MOTH. 127 



best treatment was to keep constantly working among the Turnips, 

 scuffling and running the small plough between the drills. 



" I saw paraffin oil applied on another farm with the Strawsonizer, 

 which, I believe, did little or no good. A mixture of arsenic and lime, 

 also applied with the Strawsonizer, apparently killed the caterpillar ; 

 but I did not see this done myself, so cannot speak positively about it. 



(3). " Eain did not kill or even wash off the caterpillars in my 

 case, but as it kept the plants growing to a certain extent, it did 

 good. 



(4). "Fine loam. In one field I had rather a good instance of 

 cultivation, as out of the field (which is about eight acres) two acres 

 were not ploughed till just before sowing Swedes (the field had been 

 Oats) ; the rest was ploughed in winter. The caterpillar was equally 

 bad on both bits where Swedes were sown, but hardly did any harm 

 to a strip of early-sown yellow Turnips between the two lots of 

 Swedes. Manure used farmyard and fish phosphate. The Oat- 

 stubble was ploughed about eight inches deep, and was twice ploughed 

 again before drilling. 



(5). " There was nothing in the weather to prevent cleaning the 

 land, which is singularly free from any weed. We had an extra- 

 ordinary hot dry month in February, which might be favourable 

 towards hatching moths. 



(6). " There certainly is a considerable amount of wild Mustard 

 about our land. I did not notice the caterpillar on it, but cannot say 

 I looked carefully. 



(7j. "Birds did not come much to our Turnips, but I believe 

 Peewits and Starlings are the most useful." 



(Observation). " I may mention that yesterday, in examining 

 some Turnips in a field here'' (this, forty miles from the sea, is high up 

 on the moors with hardly any arable land at all), we found the cater- 

 pillars at work in a pretty newly-hatched stage, so though they have 

 got here they are much later. They seemed to be strongest on the 

 sea-coast, and though they reached farms well inland, they were not 

 nearly so destructive. When I left Waren on Monday the Swedes 

 were looking much better, and were almost entirely free from 

 caterpillars, so I hope the worst is over." 



On the 8th of October Mr. Burden Sanderson, writing from Waren 

 House, Belford, reported : — " I am glad to say my Swedes have 

 recovered from the attack, and, though a bit later, are a capital crop. 

 I quite expected to have bad to plough them out." 



On December 23rd, in reply to my inquiries as to what the ulti- 

 mate result of attack proved to be in its efi'ect on size of roots, Mr. 



* Written from Otterburn Dene, Otterburn, Northumberland. 



