DIAMOND-BACK JMOTH. 137 



'• 26 acres yellows, where early sown and got rain, came away 

 wet, and there is practically no damage ; where later it is considerable, 

 perhaps 20 per cent. ; but taking it overhead on that field the damage 

 may be only 5 per cent., as the larger part of the field is all right. 

 This is an illustration of how diflicult it is to form any reliable esti- 

 mate, or indeed any estimate at all. 



" In this field I left about two acres of wet dirty land some way 

 into the field and pushed on with the rest; these two acres were there- 

 fore later. On both sides of this strip the crop is splendid, while it was 

 eaten very badly. 



(2). "I sowed 1 cwt. per acre of nitrate of soda on 43 acres Swedes 

 and 10 acres yellows, and 2 cwt. soot on one acre Swedes. All have 

 come away well, and done better in resisting, or rather overcoming, 

 the damage, than what was not top-dressed. Grubbing, I think, 

 has helped crops which were far on, by the rough disturbing of the 

 leaves. 



(3). " Heavy rain marked the first stoppage of damage, but I think 

 high winds and a lower temperature on the night of the 22nd of July, 

 and during the last four days of that mouth, were also of great 

 benefit. 



(4). "26 acres stiff clay, ploughed in January medium depth. 

 Manure — 4 cwt. superphosphate, 87"40 per cent. ; 4 cwt. dissolved 

 bones ; 2 cwt. nitrate. No salt. 



" 17 acres light sandy land, ploughed in April. Manure — 3 cwt. 

 bone meal ; 1^ cwt. boue fiour ; 1^ cwt. cod fish guano ; 2^ cwt. 

 superphosphate, 26 per cent. ; ^ cwt. nitrate. No salt. 



"43 acres stiffish laud, ploughed in February. Part dunged, on 

 the stubble of which 10 acres got 4 cwt. slag; 1^ cwt. bone flour; 

 1 cwt. nitrate; and 13 acres got 2 cwt. super., 37*40 per cent. ; 2 

 cwt. dissolved bones; 1 cwt. nitrate. The other 20 acres with no dung 

 got 3 cwt. super,, 37-40 per cent. ; 3 cwt. dissolved bones ; 1^ cwt. 

 boue flour ; 2 cwt. nitrate. No salt. 



(5). " The season was dry. Bainfall as follows : — 1890 : October, 

 2-61; November, 3-62; December, 1-65. 1891: January, -85; 

 February, -15 ; March, 3*14; April, 'SS. Cannot say I noticed any- 

 thing unusual in the weed line. 



(6). "Yes. 



(7). "I am told that Crows and Starlings were seen among the 

 caterpillar-eaten Turnips. I must say I saw them there no more 

 than usual; and Sparrows and smaller birds preferred the Barley." * 

 —J. A. B. 



* The following "general remarks " of Mr. Begbie's are, I think, of very ser- 

 viceable interest, relatively, not only to the effect of amount of rainfall on the 

 infestation and on the condition of the attacked crop, but also the effect of the 



