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Very few quantitative records of cable damage by agents have been published, hence, it is difficult to ascertain the extent attributable to rodents and other biological agents. Such damage is probably of relatively minor economic consequence but it can result in the disruption of a military communication at a critical time. Though bare insulated cable is very susceptible to damage by insects and rodents, cable protected by 5-mil steel tape or by 10-mil copper tape is relatively immune to animal attack. Numerous attempts are being made to replace the metal tapes by lighter weight polymeric sheaths to which insect and rodent repellent chemicals have been added. The rodent resistance of the chemically treated sheaths is usually somewhat limited because gnawing rodents possess two paits of lips, an adaptation which enables them to gnaw into material without getting any of the material into their mouths. Nevertheless, statistical analysis discloses that chemical barriers do afford some protection against rodents, and the barriers retard or prevent attack by insects and microorganisms. A well rounded research program on the protection of electrical cables from biological attack was recently initiated at the U. S. Army Electronics Command, Fort Monmouth, New Jersey. Participating laboratories are the U. S. Army Natick Laboratory, Natick, Massachusetts and the U. S. Fish and Wildlife Service Laboratory, Denver, Colorado. Research on the development of termite-proof plastics for general use, including the sheathing of electric cables, is underway at the Naval Research Laboratory, Washington, DC and at the Forest Insect Laboratory.

WAR-BORN DDT has scored another great victory in man's never-ending battle with the insect world—this time against a tremendous scourge of tussock moths in northern Idaho. Early this summer the lar...

The dye-tracer method is a useful technique for measuring spray deposits in some phases of research on aerial spraying for forest insect control. This paper describes series of simple, rapid tests for evaluating the solubility, tinctorial powers, recoverability, light-fastness, and Compatibility of candidate dyes.

It is concluded that, on economic grounds, prevention of infestation by amelioration of the site and improvement in the vigour of the trees is more likely to be practical than remedial spraying of infested trees.

Establishment of a reliable sampling method is generally recognized as a first prerequisite to any scientific study of insect populations. The method appropriate to a particular problem will depend not only upon the habit of the insect species, the type of environment, and the nature of the distribution of the insect throughout the environment, but must also meet the requirement of practicability for use under actual field conditions.

It was with some surprise that the writer encountered a representative of this rare and, until recently, little known genus, from a locality in south-eastern British Columbia. The specimen in question is a female reared at Ottawa, by officers of the Forest Insect Survey of the Division of Entomology, Irom the cocoon of a Chrysopid beaten from Engelmann spruce, Aug. 26, 1938, by Mr. D. N. Ross of the British Columbia Forest Service, in the vicinity of Bayne's Lake, B. C. The adult parasite emerged in the laboratory, Feb. 20, 1939.

The two major groups of forest insect pests requiring large-scale control measures are the bark beetles and the defoliators. Ethylene dibromide or lindane are the two insecticides generally used for bark beetle control. These are applied to the bark of infested trees with hand equipment, so there is little contamination of the environment. The method is nonetheless primitive and costly and oftentimes is not successful in stemming an epidemic. One of the most promising outlooks for tailor made, bark beetle control is the teaming of an attractant with a chemosterilant. The scope of our knowledge on these types of compounds is rapidly being brought to a state where studies on bark beetles can be profitably made.

Recent study of three Ontario Petrova specimens in the Canadian National Collection, tentatively identified as P. albicapitana (Busck), showed them to be the Virginia pitch-nodule moth, P. wenzeli (Kearfott). This insect was previously unknown outside the range of its Virginia pine host, Pinus virginiana Mill. (Miller and Altmann, 1958). Following this discovery, the Canadian Forest Insect Survey assembled nearly 300 specimens labeled as Petrova albicapitana for restudy, and among these 2 more P. wenzeli specimens were identified by the writer. With the writer's differentiation guide given below, Forest Insect Survey personnel distinguished two more P. wenzeli moths from a large group of P. albicapitana specimens reared subsequently.

Between April 18 and June 28, 1945, the birds populations on three tracts near Scranton, Lackawanna County, Pennsylvania were determined by repeated, systematic census trips. One tract ("Mile Square") comprised about 40 acres adjacent to a 1-mile trail in Spring Brook Valley, 6 miles south of Scranton. The trail extends from one edge to beyond the center of a forested area of about 600 acres that in late May and early June was sprayed by airplane with 5 pounds of DDT per acre for experimental control of gypsy moth larvae and to determine the effect of DDT upon other insects. This dosage is several times that needed for control of the gypsy moth and is the maximum considered necessary by entomologists for any forest insect pest. The second tract ("Maple Lake"), 6 miles southeast of Scranton and one mile west of Maple Lake, comprised 40 acres in an area of about 350 acres of rolling land mostly forested. The area was sprayed by airplane on June 9 with 1 pound of DDT per acre for experimental control of gypsy moth larvae and to determine the effect of this concentration on other insects. The third tract ("Check"), 6 miles southeast of Scranton and a mile northwest of Maple Lake, was a 40-acre portion of an extensive untreated forest

The organization of the Forest Insect and Disease Survey, a continuing project of the Forest Entomology and Pathology Branch, Department of Forestry,was reviewed. Typical field and laboratlory operations in entomology at regional survey units were shown. The specific subject matter of the display included: a pictorial review of field sampling and insectary procedures; aids to identification of immature insects; a method of aerial survey wing an operational recorder; the life histories of seven species of defoliators; the establishment and spread of winter moth in the Maritimes and satin moth in British Columbia; and finally, machine methods of recording Survey data and procedures used in preparing the current series of national compilation of Forest Lepidoptera of Canada.

An efficient method for collecting bark beetle eggs and young larvae has been developed at the Forest Insect Laboratory of Texas A&M University. Formerly, collection of eggs involved the dissection of host material. Clark (1965) described a method of egg and larval procurement which, although resulting in adequate production, is very laborious and time-consuming. Due to collection injuries, a large percentage of the eggs and larvae were rendered useless for laboratory rearing studies. The technique herein described eliminates host material dissection during collection and minimizes injuries and destruction of eggs and larvae. Its essential feature lies in the pre-infestation treatment of the host material, which allows the bark to be removed intact at the time of egg collection.