Suppression Tactics Research Articles

Suppression of Bark Beetles and Protection of Pines in the Urban Environment: A Case Study

Southern pine beetles (SPB), and associated bark beetles, have long been recognized as major pests of southern forests. Tactics used for controlling infestations in conventional forest settings have not proven effective at achieving area-wide control, nor are they suitable for the control of infestations in high-value stands such as homesites or wildlife habitat areas. Limited options exist for protecting high-risk uninfested pines of urban forests and often pose undesirable risks. One of the most promising areas in bark beetle research currently being experimentally tested on a largescale is the use of deterrent behavioral chemicals (semiochemicals), produced by the insects or their host trees, as biopesticides to disrupt or inhibit infestations. In addition to traditional suppression tactics instituted in an unprecedented SPB outbreak in Gainesville, Florida, a semiochemical, 4- allylanisole (4-AA), was successfully tested as a protectant of pines in residential areas. 4-AA is a host-produced compound with repellent properties to many species of conifer-feeding bark beetles. The "freak" SPB outbreak in this urban environment and successful actions taken to mitigate damage are discussed.

Effect of an Inhibitor-Based Suppression Tactic on Abundance and Distribution of the Southern Pine Beetle (Coleoptera: Scolytidae) and Its Natural Enemies

An inhibitor-based tactic can suppress southern pine beetle, Dendroctonus frontalis Zimmermann, infestations using the anti-aggregation pheromone, verbenone. However, it is unknown whether southern pine beetle and its insect natural enemies are impacted by this tactic. We evaluated potential effects by examining mean trap catches, aggregation measures, species diversity and abundance indices, and interspecific covariation between southern pine beetle and its most common insect enemies. Examination of flight and landing trap catches, before and after application of verbenone to infestations, showed that southern pine beetle and its natural enemies remained at the sites at similar densities, continued their associations, and maintained similar spatial distributions. This suggests that verbenone reduces successful colonization of unattacked trees and has no negative effect on the relationship of southern pine beetle with its natural enemies.

Suppression Tactics for Dendroctonus frontalis Zimmerman (Coleoptera: Scolytidae): An Examination of the Occurrence of Infestations Adjacent to Treatment Sites

Proliferation is the vernacular expression commonly used to describe the process of establishment of a new southern pine beetle ( Dendroctonus frontalis Zimmermann) infestation in the vicinity of an existing one. We examined the proliferation process in relation to infestations treated with two commonly used suppression tactics: cut-and-leave and cut-and-remove. Because the modes of action for these tactics have not been examined, this circumstance led to our speculation that beetles dispersing from treatment sites, especially cut-and-leave tactics, initiated new infestations (i.e., caused proliferation). In this study we (1) compared the incidence of proliferation among infestations treated by cut-and-remove and cut-and-leave tactics, (2) examined the incidence of proliferation relative to an expected value for each treatment type, and (3) evaluated the incidence of proliferation as a function of infestation size and number of adjacent infestations. Two databases containing information on locations of treated and non treated infestations occurring in East Texas were used. Using comparative statistical tests, we found no significant difference in proliferation between cut-and-leave and cut-and-remove tactics. For the range of the database, infestation size did not influence proliferation, but the number of infestations surrounding the source affected proliferation. These results do not support the contention that southern pine beetles emigrating from treatment sites result in establishment of a larger number of infestations than expected.

The development of suppression tactics for Biprorulus bibax (Heteroptera: Pentatomidae) as Part of an integrated pest management programme in citrus in inland South-eastern Australia

AbstractSuppression tactics for the citrus stink bug pest, Biprorulus bibax Breddin, were developed and implemented during 1987–1992 in four lemon orchards in southern New South Wales, Australia. Tactics were based on introduction and conservation of natural enemies (principally egg parasitoids), physical or chemical treatment of overwintering populations and strategic low rate applications of a selective insecticide. Estimated adult populations of 10–35,000/1.5 ha and 70–90% fruit damage in untreated crops were reduced to <500/1.5 ha and <5%, respectively, following full implementation of the management programme. Integrated management of B. bibax removes the need for broad-spectrum insecticides to control this pest and lessens the risk of disruption to biological control of other citrus pests.

The effects of management practices on union election returns

This paper examines the importance of management suppression tactics on union activity in the United States. NLRB data on individual certification elections which have recently become available for the period 1972–1976 are merged with structural, demographic, and industry characteristics of the 96 largest SMSAs to ascertain the role of strategy versus structure in explaining union outcomes. The measures of election-generated membership outcomes are voter participation, the margin of pro-union votes, and union wins. Union suppression practices under study include consent elections, election delays, formal objections after unions win a certification election, elections overruled because of management unfair labor practices, elections held by management petition, and the number of unfair labor practice charges per representation election. Five of the six measures of suppression are significant determinants of some facet of union expansion after adjusting for structural characteristics of the area work force.

Forest Fires in a Computer

Abstract The North Carolina State Forest Fire Management Game, a system of programs for a digital computer, provides simulated experience in fire suppression tactics and decisionmaking.

Common features of outbursts of coal, rock and gas and common suppression tactics. In Russian : BOLSHINSKII, MI UGOL, V50, N11, NOV. 1975, P26–29

Common features of outbursts of coal, rock and gas and common suppression tactics. In Russian : BOLSHINSKII, MI UGOL, V50, N11, NOV. 1975, P26–29

Optimum suppression tactics—A model and some theorems

The author presents an analytic model of tactical decision making for wildland fire suppression, which emphasizes the control line concept. After determining solutions for several representations of practical constraint conditions, he concludes that control tactices can be simulated mathematically. However, he also outlines areas requiring further work.

Optinum suppression tactics—A model and some theorems

Optinum suppression tactics—A model and some theorems

Forest Fire Problems—A Progress Report

Forest and wildland fires in the United States of America destroy about 4 million acres annually, at an estimated direct cost of about $350 million. In the state of California alone, about 270,000 acres of timber, recreation, and watershed values are destroyed yearly. Under a cooperative agreement with the U.S. Department of Agriculture Forest Service, a research group at the Operations Research Center, University of California, Berkeley, has begun a program to study the application of operations research to forest fire control systems, this paper is a progress report on that program Problem areas that have been explored to date are (1) Initial attack planning, (2) man and equipment mobilization, (3) economics of detection systems, (4) fire camp organization, and (5) fire agency communications. Although it is still too early to provide definite recommendations in these areas, certain approaches appear very promising. One of the present limitations to OR studies is a lack of fundamental knowledge about (1). The macro-physical behavior of fire, and (2) the effect of varying suppression tactics upon this behavior. Nevertheless, the problems of forest fire control provide an exciting and worthwhile area for future research.