380 



theii presence is an indication of poor soil. . The larch minmg moth, 

 Coleophora laricella, has been observed throughout the country, having 

 caused considerable injury locally in Surrey and Wales. The eucouiage- 

 ment of insectivorous birds, especially tomtits, and the removal 

 of wealdy branches in young plantations are the best means of con- 

 trolling this moth. The larch sho(jt moth, Argijresthia atmoriella, 

 occurred frequently n company with C. laricella, and in young planta- 

 tions proved iuore injurious than the latter. 



Of Aphids, Chennes pini may be controlled in nurseries by fumigation 

 with hydrocyanic acid gas or by a nicotine spray. Two spruce Aphids, 

 Chermes abietis, Kalt. {viridis, Rtzb.) and C. {Cnaphalodes) strobUobius, 

 form galls of difierent kinds [see also R.A.E., A, vi, 154]. The injury 

 these insects do is two-fold. The gall- formation they cause undoubtedly 

 reduces growth, and in some localities spruce is often badly dwarfed 

 and even killed by the continual destruction of the young shoots. 

 All these injuries, small individually, are collectively of importance, 

 and these Aphids must rank as considerable pests of spruce in Britam. 

 Unfortmiately satisfactory and practica))le remedial measures for 

 them have still to be devised. 



Pine Weevils. — Forestry Commission, London, licaflet no. 1, February 

 1920, 12 pp., 5 figs. [Received 10th July 1920.] 



This leaflet deals at greater length with three of the weevils mentioned 

 above, viz., Hylobius abietis, Pissodes pini and P. notatus. The life- 

 history and the characteristics of the attack of H. abietis are described 

 in detail. So far as is known no conifers common in Britain are 

 immune from attack, though some are preferred to others. Attack 

 should be anticipated if larvae can be fomid in the winter under the 

 bark of stumps or their roots. There are no known preventive 

 measures. Remedial measures are of various kinds. Destruction 

 of the breeding grounds by uprooting the stumps is very costly, and 

 attempts to render them unsuitable to the weevil with creosote, or by 

 barking or charring are unsatisfactory. Insecticides are practically 

 untried in Britain. Carbolineum painted on the stems of the young 

 plants gives protection, but is liable to scorch the bark. An emulsion 

 of 5 galls, milk of lime to 3 qts. linseed oil is probably better. 



Various types of traps are used : — Pine billets sticking up out of 

 pits that have been filled with layers of branches and earth, so that 

 the ends of the branches also protrude from the pit to attract the wee\dls, 

 which oviposit on the billets, the whole trap being dug up and burned 

 in the winter ; partly buried pine or spruce billets, on which the 

 weevils lay their eggs ; twigs placed on the ground and covered with 

 fresh bark to attract the weevils, which gather under them, the traps 

 being frequently renewed ; and a new type of trap in which the bark 

 of recently felled pine stumps is prised oil in large slabs and replaced, 

 when the weevils gather mider the slabs in large numbers. Hand- 

 picking in the yomig plantations is very efiective. 



Delay in plantuig a felled area until dessication and decay has made 

 the stumps unsuitable as a breeding ground is only efiective in an 

 area isolated from other plantations. Vigorous plants withstand 

 attack better than unhealthy ones, which are also more liable to 

 infestation. 



