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Maisonneuve (P.). Enquete sur le pi6geage de la Cochylis en Anjou 

 en 1914. [An enquiry into the trapping of Clysia amhiguella in 

 Anjou in 1914.]— /2ey- Vilic, Paris, xlii, nos. 1091-1092, 27th May 

 & 3rd June 1915, pp. 441-446 & 464-465. 



The control of Chjsia amhiguella by means of bait-traps is 

 advantageous, as only unskilled workers are reciuired. In 1914, 

 trapping was extensively practised in Maine-et-Loire, one manufac- 

 turer of trap-glasses delivering 300,000 glasses in that department 

 alone. The author's experiments covered 500 acres, distributed 

 throughout the region. Nothing is gained by having a glass with 

 an opening of large diameter, one of 2 J inches proving just as 

 effective as one of 5 inches. The provision of a cover placed over 

 the glass does not appear to be justified, in contrast to Feytaud's 

 experience. The difference is possibly due to meteorological con- 

 ditions. Reports were received on 68,000 traps, which collected about 

 307,000 moths in the spring trapping period. The number of moths 

 taken varied from 26 to 2,800 per acre, the average being from 440 

 to 600. A number of causes influence these results, and in the case 

 where only 26 moths per acre were taken, one reason was that the 

 replenishing of the bait-liquid only took place every fifteen days. 

 The average number of moths per trap was 4-75, which is satisfactory, 

 as each female of the spring generation may produce 100 moths of 

 the summer one. The vine harvest was exceptionally good in Maine- 

 et-Loire in 1914 and the traps must undoubtedly have been a factor 

 in producing this result. In many of the reports made, it is stated 

 that the vineyards where this control was practised were less infested 

 than others. It should however be remembered that another factor 

 was a sudden rise of temperature from the 10th to 15th August, which 

 caused a great mortality among the caterpillars. Trapping continued 

 through the month of May. On an average, a total of from 140 to 

 210 pints of bait-liquid was used per acre; vigorous fermentation is 

 very necessary. Captures do not appear to be influenced by the 

 composition of the soil, nor does the aspect of the vineyard have any 

 apparent influence. C. amhiguella is therefore apparently indifferent 

 to these factors. The variety of vine exercises some slight influence 

 on the moth, which seems to prefer the following varieties in the order 

 given : Gamay, Pinot de la Loire, Groslot, Cabernet, Othello. During 

 1914, some vinegrowers in Maine-et-Loire captured from 400 to 2,800 

 moths per acre, whereas in the author's two vineyards the figures were 

 134 and 59. Whilst the author was capturing 134 moths per acre, a 

 neighbouring vinegrower took 640 per acre. This result must be due 

 to the very careful trapping practised by the author in 1913, when his 

 catches were 1,200 and 2,400 per acre. It therefore seems that trapping 

 need not necessarily be practised throughout a given district in order 

 to be of use. The results produced by trapping during a given year 

 seem to last through the succeeding one and this should encourage 

 growers to persevere with this method without a break, especially as 

 they will have on hand their stock of glasses, etc., and need incur no 

 further expense on that score. As in previous years, the number of 

 females was several times as large as that of the males. During the 

 early days of the flight period, the number of eggs found in various 

 females ranged from 120 to 170. The incubatipn period was observed 



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