36 CLOVER. 



of my neighbours had a Clover field adjoining one of mine, not even a 

 hedge intervening. This he cut a few days later than I did mine ; his 

 second cut was certainly damaged considerably, but to nothing like the 

 extent that mine was. Again, about an acre was left in one corner of 

 my other field to be cut as ' green meat ' for the horses, and was not 

 touched until ten or fourteen days later than the other part of the field. 

 On the plot so left but little mischief apparently was caused by the 

 caterpillars. A fair second growth took place, in great contrast to the 

 rest of the field, where the second crop absolutely failed (I suppose 80 

 to 90 per cent, of the plants were killed, and the remamder so enfeebled 

 as to produce only a little autumn sheep keep). The reason I suggest 

 is that when the mowing machine cut the Clover, the stems and leaves, 

 unknown to us, were infested with caterpillars, which would be shaken 

 to the ground, or would crawl off the stems, they were on, as they 

 became withered, and naturally seek the young fresh leaves which 

 almost at once begin to be thrown up by the plant, and preying on 

 these soon destroyed its vitality ; while, in the case of the crop cut 

 later, the insects had changed, or were rapidly changing, to the chry- 

 salis state, and consequently the fresh young shoots escaped. 



"I heard of another field in this locality which was freed of the 

 pest by Rooks, but neither they nor Starlings came to my assistance." 

 —(J. F. H.) 



Prevention and Remedies. — For the most part these would depend 

 very much on the nature of the attacked crop, and local circumstances, 

 but where infestation has been noticed on beds of Nettles, Thistles, 

 or other weeds often to be found growing round fields, where there 

 would be no difficulty in rough mowing them, and burning them after- 

 wards, this would help to get rid of many chrysalids in their cocoons, 

 which presently would have sent out a new supply of infestation. 

 Similarly if the caterpillars were seen at work where the food-plants 

 could be destroyed at a little cost, it would answer to do so, taking care 

 of course that the caterpillars were not allowed to migrate during the 

 operation. 



The occasional migration (noticed by Mr. Pye) of the caterpillars 

 from one crop to another, puts them to some extent in our power. 

 Where their course is across a fairly smooth road, a boy, or a couple of 

 boys, with thick soled boots would for a very small sum so trample out 

 the migrating pests that probably few would escape. Or if the advance 

 of the caterpillars was too rapid to be wholly met in this way, pro- 

 bably the German method of digging a ditch across the line of advance, 

 so that the grubs would be collected at the bottom of it for long enough 

 for a boy running along the bottom to trample on them, would do all 

 that was needed. 



