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SoroTZKo (A.)- OTMeT-bOAtflTenbHOCTMCTaHuin aa I9l3ii 1914 roA-b. 



[Report on the work of the Station for 1913 and 1914.] Published 

 by the Entomological Station of theZemstvo of the govt, of Tula, 

 Tula, 1915, 29 pp. 



This report covers a period of two years, the weather conditions of 

 which were widely different. Euxoa segetwn, SchifP., occurred in 1914 

 in large numbers in several districts. Observations during the last 

 five years have shown that the time of the appearance of the imago 

 in spring is fairly constant, varying between the 3rd and 9th May. 

 The time of the disappearance of the moths of the first generation and 

 the appearance of the second generation was very different in 1914 

 as compared with the previous four years ; the moths of the first 

 generation came to an end in 1914 on 12th July, some 10 to 14 days 

 earlier, and the second generation appeared on 28th July, or about 

 three weeks earlier. The causes of this are to be found in the dry 

 weather and liigh temperature which prevailed in 1914. A table 

 summarising the results of observations during the last five years 

 shows that the number of the imagines attains its maximum before 

 the 4th July ; it is therefore important to keep fallow fields clean 

 at that time. The numbers of the second generation are usually 

 much less than those of the first. 



Hydroecia nictitayis. I/., did considerable damage in 1914, principally 

 to oats, about one-third of the harvest in one district being destroyed. 

 The damage was observed from the first half of June onwards. The 

 plants were withered and yellow and had a large hole in the lower pait 

 of the stem. Having left the stem, the caterpillars inhabit the upper 

 layer of the soil, whence they attack the plants at night. Injury was 

 chiefly noticeable near the boundaries of fields. In 1910 and 1911 

 the numbers of H. nictitans on the wing were small ; in 1912 they 

 formed 131 per cent, of moths caught in molasses troughs ; in 1913 

 this figure rose to 20-7 per cent., and in 1914 to 46-8 per cent, in one 

 dirstrict, to 69*1 per cent, in another, and to 83-4 per cent, in a third. 

 In 1914 the imagines were on the wing on the 12th July, a month 

 earlier than usual. There is no doubt that this insect winters in the 

 egg-stage. The eggs are laid in lines on weeds and grasses, on self- 

 sown oats and especially on rye stubbles, on which they are deposited 

 between the stem and the remnants of the leaf-sheath. The following 

 measures against this pest are recommended : — Ploughing the stubbles 

 to a depth of about 7 inches to destroy the eggs and the newly hatched 

 larvae, the making of furrows to form boundaries to the field, and the 

 use of molasses troughs in July and August. 



The weather conditions of' both 1913 and 1914 largely affected 

 various species of Apion. Owing to the early spring of 1913, the 

 weevils appeared early in April, but on the 30th April very cold weather 

 was experienced, which interfered with the growth of most plants, 

 including clover. The females began to oviposit very early, on 19th 

 May. but owing to the absence of heads of clover and to the small 

 number of flower buds at that time, the eggs had to be laid in the buds 

 of leaves, where the larvae perished ; only the larvae from eggs laid 

 a month later were able to develop. The first pupae were therefore 

 found a month later than in 1911 and 1912, viz., in the second half of 

 July, and thus the number of this pest was considerably diminished. 



