Pest Damage and Integrated Control

A broader, more comprehensive concept of forest pest management is needed to make it a really integral part of forest resource management. A generalized model structure of a forest pest management system is presented, and the major components are discussed briefly. Predictive models are the primary mechanism of information flow to decision and action in the system. General considerations affecting the kind and number of these models are discussed, with particular reference to the dwarf mistletoes. The whole-system approach to dwarf mistletoe management is urged. The focus of this symposium is on dwarf mistletoe control. Each of the symposium sections including this, the last has the word control in its title. The various papers presented thus far have covered the relevant biology of the mistletoes, their ecological relations with host trees and stands, their effects on growth and yield and some damage statistics for different host types and geographic regions, and various control techniques for prevention or amelioration of the damage to be expected. The term management has crept in at times, and this has been expanded to integrated management in several contexts. The nature of dwarf mistletoe effects on forests has made the use of these terms fairly common, in fact. But what do we really mean by integrated pest management, or integrated management of dwarf mistletoes? The concept of forest pest management the notion that destructive diseases (and insects) are an integral part of forest ecosystems, that they have both ecological and economic impacts on those ecosystems and the resource values involved, and that somehow their effects have to be kept at tolerable levels in ways compatible with forest management objectives and practices -is not new Ñ'presente at the Symposium on Dwarf Mistletoe Control Through Forest Management, Berkeley, Calif., April 11-13, 1978. Ñ'~rofessor Departments of Forestry and Conservation and Entomological Sciences, College of Natural Resources, and Entomologist in the Agricultural Experiment Station, University of California, Berkeley. (Meinecke 1916; Hopkins 1909). However, the concept has little reality in practice. The attitude of forest managers and administrators generally has been to play the game of "wait and see," followed by seat-of-the-pants decisions on action when a pest becomes obvious, intrusive, or intolerable. This attitude has affected research priorities, time schedules, and methodology accordingly. If we better understand the full meaning of integrated pest management its spacetime dimensions, the complexities and interactions of its ecological and economic components, and the social and political factors that inevitably have a part in planning and decisionmaking -perhaps we can better set our sights on the research now needed and improve the odds of getting forest resource managers and administrators to put our collective knowledge and technology to work. Our real goal should be a forest protection system that incorporates dwarf mistletoe control -and control or regulation of all other destructive agents that may be involved -into the total resource management process on a long-term, continuing basis. Let us look at the basic components of a forest pest management system. Figure 1 shows a generalized model structure of such a system (Waters and Cowling 1976). There are four basic components (enclosed by the dotted lines): (1) the population dynamics and epidemiology of the insects and diseases involved, (2) the dynamics of forest stand development, (3) the socioeconomic impacts of pest-caused damage on resource values, and (4) the treatment strategies. Each component is a complex subsystem in itself; each requires detailed analysis and