DIAMOND-BACK MOTH. 121 



maximum value of a full well-grown plant of Swedes in Norfolk and 

 Suffolk at Michaelmas valuation, the greater part of the Gorton crop 

 was entirely destroyed, while the remainder (with the exception of one 

 piece, which was sown very early, and appears to have been too forward 

 for the caterpillar to attack) cannot be more than one-third of a full 

 crop under the most favourable circumstances ; while the Whitling- 

 ham crop being attacked about three weeks later than Gorton, the 

 heavy rains coming at the same time washing in a good dressing of 

 nitrate of soda and salt, appears to have at once stopped the ravages 

 of the pest, but not before they had checked the growth oi the plants, 

 so that under the most favourable circumstances there cannot be much 

 more than half a crop. 



(2). " Nitrate of soda and salt, about four stones per acre of eiich 

 sown by hand along the drills, were very effective m setting the plants 

 growing ; and a scuftier tilled with boughs was tried at Gorton and 

 answered very well indeed ; as also four to six gallons of paraffin per 

 acre applied with the Strawsonizer. We should have tried soot and 

 lime had not the ravages been stopped ; should also have walked a 

 flock of lambs backwards and forwards over the plants, which, I 

 believe, would be very beneficial and would act as a scuffler, and would 

 not injure the Turnips. 



(3). " Every benefit to be derived from heavy rains— in fact, I 

 much question whether the pest could be entirely destroyed by any 

 artificial means without them. 



(4). " The land at Gorton is a strongisli top soil on yellow clay, 

 and owing to the exceedingly dry weather up to October and frost and 

 snow afterwards, was not ploughed or cultivated until latter end of 

 February or the beginning of March, and then only ploughed fleetly. 

 In some cases the manurings for Swedes were town manure, fish refuse, 

 with a good proportion of salt, mixed up together and put on at the 

 rate of ten loads per acre, while in others 4 cwt. of mineral super- 

 phospate and half cwt. of nitrate of soda were applied before the attack. 

 At Whitlingham the surface soil is a good light soil on brick earth, 

 and was cultivated in the autumn, and ploughed a good depth in the 

 spring before putting in the Swedes. Some fields were manured with 

 ten loads of farm manure, and others with 4 cwt. of mineral super- 

 phosphate per acre. 



(6). "Exceedingly dry up to October, and where stubbles were 

 broken up during harvest or immediately after (before the land got 

 too hard and dry for ploughing), gave farmers a good chance of 

 cleaning the land. 



(6). " Have no experience of Gharlock. 



(7). " Gannot say anything as to what kind of birds are especially 

 useful in clearing away the caterpillars." 



