194 TURNIPS. 



Prevention and Eemedies. — Almost the only method of 

 lessenmg amount of damage from presence of these caterpillars 

 appears to be from natural or artificial applications suited to 

 drive on growth. 



On August 8th, in 1883, Mr. H. Stourton, of Holme Hall, 

 near York, writing of a bad attack in the district, mentioned 

 that he put on nitrate of soda and soot — and on the 21st of 

 the same month, whether from favourable weather for growth 

 having occurred, or from the use of the fertilisers, " some of 

 the damage was being repaired." 



In the South African observations, sent me by Mr. J. de 

 Witt Meulen, of the Winterhoek, he noted, " heavy rains or 

 frequent watering of the leaves destroys many grubs." 



The best note of stopping attack l)y dressings was sent me 

 by Mr. Henry Eoss, from Chestham Park, Henfield, Sussex, 

 in the autumn of 1889. The attacked Kale on the 30th of 

 September was only about an inch high ; I suggested Mr. 

 Fisher Hobbs' dressing (see p. 190) applied when the dew loas on, 

 so that the dust should adhere to the leaves, but soot alone 

 proved sufficient. Mr. Eoss reported that he used soot 

 lavishly (100 bushels per acre sowed broadcast) : — We were 

 fortunate in our weather — a humid morning, every leaf 

 holding moisture, and the plants went off at a jump ; and 

 on the 13th of January the Kale was reported to have been 

 growing ever since, and to look most kindly. 



The plan of brushing the infested plants with boughs fixed 

 on a scuffler has been found to answer in some cases. The 

 Diamond-back caterpillars let themselves down by a thread 

 when alarmed ; consequently, by the passage of the scuffler 

 after the boughs, many must get destroyed on the ground. 



The caterpillar also feeds on other plants of the Cabbage 

 Tribe, as the very common " Jack-by-the-Hedge," "Wall 

 Mustard " and others; and where the cocoons are observed in 

 great quantities on large weeds by field sides, it would be well 

 to have the plants drawn or, where practicable, rough mowed 

 and destroyed ; also where, as sometimes happens, a crop is 

 totally ruined, it would be well to plough it thoroughly in at 

 once before the moths could develop out of their cocoons, and 

 fly to cause attack on neighbouring Turnip or Cabbage fields. 



Turnip Sawfly. AthaUa spiudrnin, Fab. ; A. cntifolm, Panzer. 



The caterpillars of this Sawfly, which are known under 

 various names, as "Blacks," "Black Palmers," "Niggers," 

 &c., appear from time to time in very large numbers, and do 

 serious damage, sometimes clearing the leafage of a whole 



