Genetic diversity rarely makes headline news. Whereas species extinctions, loss of old-growth forests, and catastrophic forest fires are readily grasped public issues, genetic diversity is often perceived as arcane and academic. Yet genes are the fundamental unit of biodiversity, the raw material for evolution, and the ultimate source of all variation among plants and animals on earth (Dobzhansky 1970, Soulé and Wilcox 1980). Why then have they escaped central attention in conservation? Although genes are pervasive, controlling individual fates and determining ospring destinies, they are minuscule molecules, unyielding to meaningful direct observation even through a microscope: their direct structures and functions are essentially invisible. Over the decades we have learned about their existence and significance indirectly by studying the eects that genes have on individuals, populations, and species. Because genes are passed among generations in mathematically predictable ways, we have developed a towering theoretical understanding of the way genes ought to work in nature (Wright 1978). Increasingly we are able to penetrate the nature of genes directly, through biochemical and molecular analysis (Figure 14.1; Nei 1987, Neale and Harry 1994). We are beginning, dimly, to perceive empirical connections between changes in gene pool diversity and species declines, changes in forest health, and loss of ecosystem productivity. This cumulative knowledge teaches us that attention to genetic diversity will pay off in achieving the goals of forest conservation.

With an emphasis on North American conifers, this chapter presents general approaches to conserving forest gene pools and provides examples illustrating how genetic management can be integrated within other conservation efforts.