556 



All trees that are felled for traps should have their branches cut off, 

 otherwise the sap will evaporate too rapidly through the foliage. The 

 large branches should be laid beside the trunks and treated exactly in 

 the same way, and will thus form additional traps. If there is no use 

 for the small branches and twigs, these can be left on the ground, as 

 their reserve of sap is not sufficient for development of the larvae. 



The author's experience has been that the cost of the treatment is 

 covered by the value of the felled trees as timber, while the number 

 that are cut down for traps is no greater than those felled during 

 thinning, which becomes necessary every six or eight years. 



Badoux (H). Pests of the Weymouth Pine in Switzerland. — Jl. 



Forestier Suisse, Berne, Ixxii, no. 9, September 1921, pp. 163-173. 

 (Abstract in Internal. Rev. Sci. & Pract. Agric, Rome, xii, no. 11, 

 November 1921, pp. 1500-1502.) [Received 11th September, 

 1922.] 



Though long supposed in Switzerland to be immune, the Weymouth 

 pine {Pinus strohus) is attacked by a number of enemies. 



An Aphid, Chernies [Pineus) strobi, Htg., has frequently appeared of 

 recent years in stands 30 years of age or older. Coleopterous pests 

 include the Scolytids, Xyloterus lineatus, Oliv., in felled, but unbarked 

 logs, Pityophthonis micrographus, L., in branches and small trunks, 

 and Pityogenes {Tomicus) quadridens, Htg., Myelophilus piniperda, L., 

 and M. minor, Htg., in the trunk and shoots. Plantations are 

 occasionally much damaged by the weevil, Hylobius abietis, L., and 

 trunks infected with the fungus, Peridermium strobi, sometimes harbour 

 Pissodes pini, L. The larvae of the sawfly, Diprion {Lophyrus) pini, L., 

 have appeared regularly for years towards mid-September upon 

 Pinus strobus growing in the garden of the Zurich Forestry Institute, 

 but without doing any great injury. The moth, Dioryctria splendidella, 

 H.S., has been recorded since 1919 in stands infected with Peridermium 

 strobi, and increases the injury done. Otherwise it is unimportant, as 

 it only attacks trees already diseased. 



Theobald (F. V.). Thrips in Corn. — Reprint from //. Kent Farmers 

 Union [sine locol, xii, no. 2, August 1922, 2 pp. 



Limothrips cerealium, Hal., and L. denticornis, Hal., seriously 

 damaged wheat in Kent in 1922, and occasionally oats and other cereals 

 were attacked. The tips of the ears, where the insects feed, become 

 pallid and no grain forms in the attacked portions, and it is found when 

 the corn is threshed that the maturing grain has shrivelled. Breeding 

 takes place in the ears, and all stages may be found simultaneously 

 there. The winged adults fly about periodically, generally in sultry 

 weather. They may be carried by the wind for considerable distances. 

 As the corn ripens the thrips gradually leave it, being unable to penetrate 

 the ripe kernels. They seem to pass the winter either as pupae or 

 adults, generally in the soil, or in hollow stalks or among grasses and 

 stubble. Besides wheat L. cerealium attacks oats, and L. denticornis 

 barley and rye. They often cause severe damage on the Continent, 

 where a third species, Frankliniella tenuicornis, also attacks barley. 



The only method of checking infestation is by early sowing and the 

 destruction of hibernating insects. The earlier spring oats are sown, 

 the more likely they are to escape injury from thrips and also from frit- 

 fly [Oscinella frit]. It is suggested that all stubble should be harrowed 



