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Beeson (C. F. C). Forest Insect Conditions in India. — Agri. Jl. 

 India, Calcutta. Special Indian Science Congress Number, 1918, 

 pp. 114-124. [Received 30th September 1918.] 



This paper compares the primary pests of Indian forests with those 

 of other countries, particularly those of the temperate regions of 

 Europe and North America. 



In Central Europe the principal primary pests are mainly those 

 of coniferous trees, the most important defoliators being : — Lymantria 

 monacha, L. (nun moth), the outbreaks of which generally last for 

 from 5 to 7 years, being accompanied by the total destruction of spruce 

 and pine forests over wide areas ; Demlrolimus pini, L., the most 

 important enemy of Pinus sylvestris ; Bupalus piniarius, L. (pine 

 looper) and Panolis (iammea {griseovariegata, Goetze), both dangerous 

 defoliators of pine woods, the last outbreak of the former in 1892-96 

 resulting in the clear felling of over 150 square miles of pine forest 

 in Bavaria. In the United States coniferous defoliators are not 

 numerous, the most injurious being Lygaeonematus (Nematus) 

 erichsoni, Hart, (large larch sawfly), which, since 1880, has killed off 

 50-100 per cent, of the mature larch over vast areas in the north- 

 eastern United States. In Canada this sa^vfly has also proved to be 

 a serious pest of Larix americana and other larches during the last 

 20 or 30 years, killing off practically all the mature trees in Eastern 

 Canada; Tortrix fumifemna, Clem, (spruce budworm) has done great 

 damage to balsams and spruces, especially in eastern Canada, and to 

 Pseudotsuga taxifolia {dotiglasi) (Douglas fir) in Vancouver Island ; 

 Neophasia inenapia, Felder (pine butterfly) has also been injurious. 

 In British India the conifers and evergreen oaks of the moimtain 

 forests appear to be entirely free from fatal primary defoliation. 



Hardwood trees in Europe are fatally defoliated, especially beech 

 and oak, by Lymantria (Porthetria) dispar, L. (gypsy moth), Arctornis 

 chrysorrhoea, L. (gold-tail moth) and Nygniia phaeorrhoea, Don. 

 (bro^vn-tail moth). In the United States the greatest local defoliator 

 is Lymantria dispar, introduced from Europe in 1868, and now 

 thoroughly established in forest areas. In Canada forests of both 

 coniferous and broad-leafed trees are also threatened by Nygmia 

 phaeorrhoea, introduced 12 or 15 years ago and now endemic in Nova 

 Scotia, and epidemic in the boreal parts of New Brunswick. In 

 British India many Lepidopterous defoHators of hardwoods are 

 known and widespread. Hyhlaea puera, Wlk., Pyrausta machaeralis. 

 Cram., and several species of Arctiids periodically, and in some cases 

 annually, defoliate forests of teak throughout the whole of its distri- 

 bution. As complete defoliation of teak is however followed by a 

 rapid renewal of the crown foliage or by temporary production of 

 epicormic shoots, the injury is restricted to loss of increment and 

 occasional stagnation. 



The most important bark-borer beetle of coniferous forests in 

 Europe is Ips typographus, L., other pests including the weevil, Hylobius 

 abietis, L., and the cockchafers, Melolontha tnelolontha, L., and 

 M. hippocastani, F. North American coniferous forests suffer from 

 extensive invasions of the Scolytids, Dendroctonus frontalis, Zimm. 

 (southern pine beetle) and D. piceaperda, Hopk. (eastern spme^ 

 beetle), which have killed off spruce over thousands of square j?^['d^^*'^''^'^ ^'^'tifj^ 

 (C523) Wt.P2/137. 1,500. 12.18. B.&F.Ltd. Gp.11/3 /^ A ''^ 



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