76 EXPERIMENT STATION RECORD. 



all rubbish, planting squashes as trap crops, and spraying melon seedlings with 

 Bordeaux mixture. 



Leather-jacket grubs {Jour. Dept. Agr. and Tech. Tnstr. Ireland, 4 {1904), No. 4, 

 pp. 719-721, figa. #). — The larvae of crane Hies arc said to he serious pests in grain 

 fields and meadows in Ireland. Careful plowing and the use of fertilizers are recom- 

 mended in controlling these pests. 



Grasshopper and cricket outbreaks, J. M. Aldrich (Idaho Sta. Bui. 41, pp. 

 289-304, pi- l,figs. $).— The Rocky .Mountain locust was not concerned in any of the 

 recent outbreaks in Idaho. The most important species was Camnula pellucida. 

 The most serious outbreaks occurred on Big Camas prairie and near Market Lake. 

 The duration of a locust plague appears to he about 5 years, and is apparently brought 

 to an end by the combined action of the natural enemies of the locust. 



Experiments with the South African grasshopper fungus were quite unsatisfactory. 

 An experiment with crude petroleum showed that the locusts could be destroyed by 

 the use of this remedy but that the method was too expensive. Burning under straw 

 w r as recommended and also the use of hopperdozers. The author also mentions such 

 remedies as plowing under the eggs, the use of irrigation ditches, and poisoning with 

 the Criddle mixture. 



An account is presented of the depredations of Anabrus simplex. This cricket 

 hatches most extensively in arid foothills and feeds on sagebrush. The pest has 

 been kept off from cultivated tields by the use of irrigation ditches and by driving 

 in swarms. 



Control of the brown ant (Solenopsis geminata) in orange orchards, I >. YV. 

 Barrett (Porto Rico Sta. ('ire. 4, pp. 3). — This ant normally feeds on the honey wax 

 secreted by scale insects. Under certain conditions, however, it attacks citrus trees, 

 causing an excretion of gum upon which it feeds. The ants also attack the flowers, 

 young fruit, terminal buds, and small twigs. In order to prevent the ants from 

 ascending the trees it is recommended that the trunks of trees be painted with a 

 mixture containing a yellow resin, linseed oil, and tobacco decoction. For destroy- 

 ing the ants in their nests the use of a mixture of resin 2 parts, sal soda 1 part, and 

 tobacco decoction 1 part is recommended. This mixture may be applied directly 

 in the galleries of the nests. This circular is issued in both English and Spanish 

 editions. 



The chemical composition of some insecticides for the potato beetle, R. 

 Harcourt (Ontario Agr. and Expt. Union Rpt. 1903, pp. 59-62). — An account is given 

 of the proper composition of Paris green with notes on its use as an insecticide, 

 especially in the control of potato beetles. The author discusses the use of London 

 purple, lead arsenate, slug shot, Bug Death, and certain other proprietary insecticides. 



Paris green spraying experiments, J. K. Haywood ( U. S. Dept. Agr., Bureau 

 of Chemistry Bui. 82, pp. 32, pis. 2). — The experiments reported in this bulletin were 

 undertaken for the purpose of determining how much soluble arsenious oxid may 

 be present in Paris green without injuring the foliage. It was found that the soluble 

 arsenious oxid in a sample of Paris green may be of two kinds, viz, that which is 

 readily soluble in water and that which becomes soluble by decomposition of poorly 

 made Paris green. 



Samples of Paris green were obtained and the amount of soluble arsenious oxid 

 carefully determined. The amounts of soluble arsenic were then artificially increased 

 if necessary so that samples were obtained which contained amounts varying from 

 2.24 to 8 per cent. As a result of numerous spraying experiments it is concluded 

 that the following amounts of soluble arsenious oxid are safe when sprayed without 

 the use of lime, viz, for apple trees, 6 per cent; for pear trees, 6 per cent; for plum 

 trees, 4 per cent, while with the use of lime the following amounts are regarded as 

 safe, viz, for apple trees, 7 per cent; for pear trees, 7 per cent; for plum trees, 5 to 6 

 per cent; and for peach trees, 4 to 5 per cent. 



