Spruce budworm control

Assessment of the effects of the 1977 New Brunswick spruce budworm control program on fish food organisms and fish growth" Montreal Engineering Co. Ltd. Fredericton, N.B., 1978. 

Phosphamidon. Phosphamidon was introduced into Canadian spruce budworm control programs in the mid-60s to reduce the adverse effects on aquatic organisms, particularly Atlantic salmon stocks, which had accompanied the use of DDT in previous programs. Its relatively low toxicity to fish led to the application of phosphamidon within buffer strips along streams and rivers inside large DDT spray blocks. These protective measures greatly reduced fish losses within DDT treated areas (20). Phosphamidon has also been shown to have only limited effects on aquatic insects (21, 22). 

Holmes, S.B. "Aquatic impact studies of a spruce budworm control program in the lower St. Lawrence region of Quebec in 1978" Report FPM-X-26, Forest Pest Management Institute Sault Ste. Marie, Ont., 1979. 

Buckner, C.H. Sarrazin, R. "Studies of the environmental impact of the 1974 spruce budworm control operation in Quebec" Report CC-X-93, Chemical Control Research Institute Ottawa, Ont., 1975. 

When abscisic acid is applied to balsam fir, the break of buds in the spring is delayed and the emerging spruce budworm, Choristoneura fumiferana, larvae are forced to feed on old needles, which are a less desirable food. Attempts have been made, rather unsuccessfully, under natural forest situations, to manipulate budbreak with growth retardants for the control of the spruce budworm. However, this system seems to operate under controlled greenhouse conditions, and with some adjustments, it may have potential for practical applications in the field (32). 

DDT, discovered by Dr. Mueller in Switzerland, and used for insect vector control during World War II, quickly found a place in forestry, as well as agriculture. The material proved highly effective in the control of such insects as the spruce budworm, tussock moth, hemlock looper, and many others. It was widely used in the Northeast for control of the introduced Gypsy moth during these early years. The low toxicity of DDT to mammals made it to appear to be an excellent insecticide for forestry use. It was only after subsequent studies revealed the impact on other species that reservations about its use was raised. 

The chemical and behavioral aspects of the sex pheromones of several forest defoliating insects of economic importance in eastern Canada are presented, with emphasis on the spruce budworm, Choristoneura fumiferana. Studies conducted over several years in New Brunswick on the use of pheromones as potential control agents, using in particular the air permeation technique to effect mating disruption, are discussed. The identification and the behavioral effects of minor components of the spruce budworm pheromone system are presented and the potential exploitation of their behavioral roles in the mating sequence in terms of control strategies are addressed. 

This paper will review the uses of pheromones for detection, monitoring and possible control of eastern forest Lepidoptera. As an illustrative example, particular reference will be made to the control of the spruce budworm, the techniques used and the problems involved including limitations due to economics and lack of biological information on this species. 

As in most Lepidoptera, spruce budworm males locate conspecific females by flying upwind along a pheromone plume. The blends and release rates of these pheromone components form an important part of a specific communication system for the species. Once the communication system of an insect is understood, especially the pheromone chemistry as it relates to male behavior, it can be used in a variety of ways. For example, pheromones can be used to detect the presence of an insect in an area, to remove males from a population by trapping or poisoning and in air-permeation techniques in which the controlled and continuous release of pheromone components in the forest can disrupt mating. The latter use of pheromones appears to alter the normal male behavioral responses to the natural pheromone (16). 

Hurtig, H.J. Fettes, J.J. Randall, A.P. Hopewell, W.W., "Field and Laboratory Investigations of the Effectiveness of Insecticidal Sprays Applied from Aircraft in Controlling Larvae of Spruce Budworm (Chroistoneura fumiferana (Clem))", Rep. No. 176, Suffield Exper. Sta., Alberta, Canada, 1953 ... 

Barry, J. Ciesla, W. Ford, R. Luebbe, R. Whitcombe, L. Young, R., "Spray Deposit Maine 1976 Operational Project for Control of the Eastern Spruce Budworm Comparing Effectiveness of Sevin 4-oil 3/4 and 1 pound per acre" USDA For. Serv., Methods Application Group, Davis, CA. 1976. 

Insecticides are also used on a large scale to control a few lepidopterous defoliators of mature conifers including spruce budworm. 

Table 1. Insecticides used operationally and areas treated aerially for control of the. spruce budworm in E. Canada during the period 1967-1982- -...

Spruce Budworm in E. America USDA Ag. Handbook, in Press and reports to the Canadian Forestry Service Annual Forest Pest Control Form. 

The insecticide aminocarb has also been used extensively in eastern Canada on budworm control operations. Fenitrothion has been applied as a water emulsion (New Brunswick) and an oil solution (Quebec), but aminocarb because of its formulation characteristics, has been only applied operationally as an oil solution. Analysis of spruce foliage (7) showed aminocarb had a half life of 5 to 6 days with complete disappearance by 64 days post spray. Subsequent work (8) confirmed the short half life of aminocarb on coniferous foliage (3.2 to 6.9 days), and showed that the half life was dependant on the initial concentration of the insecticide. The material was found to be highly labile and dissipated rapidly and the authors made the statement that with these characteristics... 

The aerial application of insecticides for budworm control results in the deposition of insecticide on the foliage and on the forest litter the proportions of the spray being deposited can be related to tree species (fir collecting more than spruce) and the fate of the insecticide. DDT became a problem of concern partially because of its long residual life, since its withdrawal from use the presently used insecticides, fenitrothion and aminocarb are characterized by their rapid initial disappearance. Although aminocarb cannot be found chemically relatively shortly after the spray application, fenitrothion residues at very low levels can be found for a long time (up to one year) after spray application. Gardona, acephate and chlopyrifos-methyl are also characterized by a rapid initial loss. 

Chemicals have been an important means of controlling forest insect pests in Canada for the past four decades. They have been used to limit the impact of some of the most destructive forest pests, such as spruce budworms (Chovistoneuva spp.), on forest resources essential to the production of fibre and other forestry products. With growing demand for these products, pest control... 

The fate of fenitrothion in the environment has been a subject of great interest in Canada since the late 1960 s because of its use for control of the Spruce Budworm (Chorlstoneura fumiferana). Laboratory and field experiments have established that fenitrothion persists for only 1 to several days in natural waters and is degraded primarily by photolysis and microbial activity (1-4). Sorption by sediments, aquatic macrophytes and microphytes are also important paths of loss of the insecticide from the water column (2-5). 

Uses nonsystemic, broad-spectrum insecticide used to control the spruce budworm in forests and also as molluscicide. 

Model model (15.7) has originally been introduced to model insect pest outbreaks of the spruce budworm Choristoneura fumiferana [25]. This forest defoliator lives in the spruce and fir forests of north US and Canada. The budworm population can be either in small numbers (rest state) which are under predatory control by birds. Around approximately every 40 years it comes to an outbreak in the budworm numbers (excited state). Then the insects develop to a pest that can defoliate the trees with enormous environmental and economic damage. 

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