DIAMOND-BACK MOTH. 1J7 



dashed the sand and mud on to under side of leaves, and made the 

 life of the caterpillar no sinecure. 



(4). " My laud all natural Turnip land ; loam with sand, or sandy 

 loams and clay loams. First field attacked was twice scarified in the 

 fall of 1890, and all stubbles and weeds raked off; deeply ploughed 

 (8 in.) in February, and again in May, and dunged in drills. Where 

 rotted dung was applied, the plants have outlived the attack ; where 

 courtyard duug (fresh), the plants all perished, 



(5). " Fine autumn till 20th October ; after that, till 1st December, 

 very wet. No particular weeds. 



(6). " Scarcely any Charlock on farm ; Couch the chief weed. Will 

 send specimens of two weeds which prevail. 



(7). " Starlings, Sparrows, Chaffinches, and Linnets very plentiful, 

 and all been most industrious." 



Oct. 6th. Estimate of damage resulting from attack: — " The first 

 field of Swedes is so extravagantly luxuriant in shaws [Anglice, Tops) 

 as to lead the casual observer to conclude, ' No harm done ; splendid 

 crop.' But examine the shaws or top leaves, and you fiud a double 

 number; the outer rows are the original perforated leaves, in the 

 centre of which have grown up a later or new set of stems and leaves ; 

 but examine the bulb, and you find it half the size. The same applies 

 to the yellow varieties that are left. One-third of an average crop, in 

 weight of bulbs, is rather under than over the deficit." 



On Dec. 23rd, Mr. Swan, in reply to my inquiries as to what the 

 amount of loss might have proved to be when time of storage or use of 

 roots arrived, favoured me with the following details, which I give in 

 extenso, as they meet several considerations of useful interest. The 

 amount of loss ; the enormous growth of leafage, so misleading to 

 those unacquainted with the bearings of this shaw for service ; the 

 very peculiar method of start of the second growth of leafage ; and the 

 serviceableness of sowing Rape-seed to fill in amongst the damaged 

 Turnips. Mr. Swan wrote : — 



"First, as to Swedes; I had a firm conviction all through 

 September, October, and November that we were to have a great 

 deficiency in bulbs. The leaves, perforated in July, partly fell ofl", but 

 a large portion remained, and out of the centre of the first shaw a 

 second growth of leaves sprang up, and where the land was in good 

 condition, whether clay, clay-loam or black land, or sandy loam, all 

 through October not a drill could be distinguished, so rich, rank, and 

 luxuriant was the foliage. 



" I was set down as a * growler ' by a party of friends when they 

 looked over a field of 25 acres, and before they walked into it ; that 

 field is now, at date, two-thirds cleared, and the produce is 14 loads — 

 perhaps, I may say, tons — as against 28 to 30 seven years ago, being 



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