237 



weevil) in yams from Jamaica ; a scale, Lepidosaphes alba, Ckll, on 

 cassava from the Bahamas ; and Pseudococcus sacchari, Ckll. (sugar- 

 cane mealy-bug) on sugar-cane from Cuba. 



Green (F. J.). The Larch Shoot- boring Moth.— ^^^^ Jl- Forestry, 



London, xiv, no. 2, April 1920, pp. 119-122. 



The insect enemies of larch in England are of great economic 

 importance, as this is one of the staple trees for timber production. 

 Lygaeoneniatus (Nematus) erichsoni (large larch sawfly) can be checked 

 to some extent by hand-picking the larvae and by encouraging 

 insectivorous birds in the woods and nurseries. The most injurious 

 pest is Argyresfhia laevigateUa (larch shoot-boring moth). The 

 moths appear from about the second week in May in warm countries 

 and in June in northern or colder localities. Pairing and oviposition 

 oocur soon afterwards, the eggs being laid on the young shoots. The 

 larva hatches in June or July and, boring its way into the shoot, 

 begins to tunnel and feed. It hibernates in the shoot and in early 

 sprmg resumes feeding until May, when it pupates after boring a 

 small exit hole through which the adult escapes. Damage done by 

 this insect is frequently attributed to frost, especially when there is 

 also an infestation of Coleophora laricella (larch mining moth) which 

 bores into and kills the needles. Young larch trees, ten or twelve 

 year^ old, are the most severely attacked. Japanese larch is objected 

 to m some locahties owing to its habit of growing multiple leaders, 

 but the author attributes this in many instances to an endeavour to 

 replace a leader destroyed by A. laevigateUa, whereas in native and 

 European larches only one shoot is sent out to replace an injured 

 leader. 



Control measures are difficult to carry out, but much can be gained 

 by restricting the planting of larch to soil and locahties suited to it, 

 and by planting only strong plants with an abundance of fibrous 

 roots. Insectivorous birds should be encouraged. In early sprint, 

 before the moths appear, affected shoots, distinguishable by their lack 

 of foliage, should be cut out and burnt. The soil surface should be 

 kept free from dead poles and branches. Initial thinning should 

 be practised soon after the surface vegetation is suppressed, "and this 

 thmmng should be consistent with a close overhead canopy so as to 

 conserve the soil moisture and preserve the soil fertihty. 



Marshall (R. C). The Pine Beetle in the New Forest.— Q/Y%. Jl. 

 Forestry, London, xiv, no. 2, April 1920, p. 142. 



Scots pines {Pinus sylvestris) in the New Forest have been exten- 

 sively attacked by the pine beetle, Hylurgus piniperda. The beetles 

 hibernate in the rootstock and occasionally in the hollowed-out 

 shoots. Breeding occurs in dying or felled "timber, especially jjine 

 logs that are lying about unbarked, and the larvae hatch in two or 

 three weeks, the beetles appearing in June and Julv. There may be 

 two generations in a year. Scots pine and occasionally larch are 

 the only food-plants. The remedies are the eradication of breeding 

 places and the provision of suitable breeding traps in which the 

 beetles may be destroyed. 



