66 EXPERIMENT STATION EECORD. 



The oak scale insect, J. Ritzema Bos {Tijihrhr. I'lantenziclden, 7 {1901), No. 5-6, 

 pp. 14I-I45). — ^^7^v«//(^sy>/^wy»^/y■/^o/rt i.s report('<l an attacking the native as well as 

 introduced oaks in Holland. The injury from this species has not yet reached any 

 alarming proportion, but attention is called to it in order that reports may be made 

 and operations liegun against the species if it becomes too numerous. 



Th.e oak flea-beetle (Haltica erucae), J. Ritzema Bos {Tijdschr. Plantenzielien, 

 7 {1901), Xu. o-fj, pp. 129-141). — Notes are given on the habits and life history of 

 this species of flea-beetle, which is reported as attacking a number of species of oak. 

 The insect appears every year, but not always in large numbers. When the larvfe 

 and beetles occur upon the leaves they may be destroyed by sjiraying with kerosene 

 emulsion or with arsenical poisons, but these methods are ordinarily too expensive. 

 A cheaper way of combating the insect consists in attacking the beetles during the 

 winter. They may usually Ije found concealed in rubbish and in the cracks of old 

 bark upon the trees, and by scraping off the loose bark and burning it, together with 

 other rubbish, the beetles ina)^ be readily destroyed. 



Insect enemies of the pine in the Black Hills Forest Reserve, A. I). Hopkins 

 ( r. S. Dept. Agr., Dirmon of Entomoluf/y Bui. S2, n. .s-er., pp. 24, j'lx. 7,figi^. 5). — In 

 this bulletin a report is made on a study of the insect enemies of the rock pine {P'nrus 

 pondn-osa scopuloruni) in the Black Hills. The attention of settlers was attracted to 

 the extensive destruction of this tree by insects about 1895. The species of beetle 

 which is chiefly concerned in killing the pines is described as a new species, under 

 the name Dendroctonui^jionderosa. After the primary attack is made by this species, 

 several other species of beetles may also set to work upon the trees and cause a more 

 rapid death and decay. Among the latter species brief notes are given on the fol- 

 lowing: 7'omyV-«.s oreyimj, T. cuUigntjthun, T. cnlatua, Dendroctoiin.i vaJena, llylurgops 

 sxihcoHtulatus, and Ilylaste^ porosua. A number of small pine trees were dying appar- 

 ently of other causes which were not definitely determined. Among the natural 

 enemies of I), ponderosa special mention is made of Trogosita viresceyis, and certain 

 other predaceous l)eetles and bugs. No parasitic insects of any importance were 

 found i)reying upon the pine beetle, nor did i)arasitic fungi or birds appear to exer- 

 cise any imjiortant influence in checking the work of the pine beetle. 



According to the observations of H. E. Dewey and the author, the l)eetles migrate 

 from dying trees in swarms during August, and settle on living trees, which they 

 attack from near the base to the upper part of the trunk. The first indication of the 

 infestation is the presence of red dust in the loose bark or at the base of the tree; 

 this is followed by the appearance of numerous small masses of pitch on the surface 

 of the bark. After the tree is once thoroughly infested other insects and fungi cause 

 its rapid destruction. It appears that unless trees are cut within 2 or 3 years after 

 they begin to die very little of value is left. The attack of this species is apparently 

 becoming less serious. 



The author recommends, in combating tliis insect, that the location and extent of 

 infested areas be determined, after whi('h the infested trees in these areas should be 

 marked for cutting. Contracts for cutting trees should specify that only infested 

 trees should be cut. An investigation of railroad ties which were cut according to 

 contract on account of being infested with the insect, showed that only 55 out of 207 

 ties showed any evidence of having been attacked by the beetle. It is suggested 

 that further experiments be conducted in cutting and removing the l)ark from 

 infested trees, and in girdling and otherwise treating living trees so as to make them 

 serve as traps for the ])eetles. 



Some insect enemies of living- trees, A. D. Hopkins {Proc. Soc. Prom. Agr. 

 Sci. 1901, pp. 66-69). — Brief notes on Ihndroctonus }>revicornh, D. monticola, D. 

 pseudotsmgse, D. plceuperda, and other common insects injurious to forest trees. 



The shade-tree insect problem, A. H. Kirkland {Massachusetts State Bd. Agr. 

 Rpt. 1901, pp. 77-107, pis. ii,figs. S). — This was a paper read before the State Agri- 

 cultural Society and is concerned witli a discussion of the habits, life history, and 



