The war on weeds in the prairie west: an environmental history

In Chapter One, Evans examines changing definitions of weeds. Over the past two centuries, nuisance plants have been defined differently, and by recognizing and invoking the different definitions, historians can understand the botanical intruders as agents of change as well as a type of plant. Weeds, Evans notes, are both located in subjective categories and rooted in objective biological facts. While weeds can be viewed simply as "plants out of place," they are also a specific group of species that have evolved alongside agriculture. The species share some common attributes: great intra-species genetic and phenotypic variation, "a high degree of environmental tolerance," and " 'weedy' reproductive strategies," including dormancy, sexual-asexual reproduction, and great numbers of seeds (p. 6). According to Evans, weeds are both "cultural artifacts" and "active participants in culture" (p. 17).