This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This study chronicles the course of an important but little known Canadian war: the war between people and weeds in Western Canada. Arising from intense competition between two groups of immigrants, this conflict started in Europe, spread to Eastern North America and reached a climax on the broad expanses of the Canadian Prairies. By the early 1940s weeds had gained the upper hand on their human competitors and many predicted the end to extensive grain production in the West. This did not occur, however, because of the timely development of 2,4-D and other selective herbicides immediately following the close of World War II. These potent chemical weapons gave prairie farmers new hope at a time when defeat seemed all but certain and they are largely responsible for the expensive standoff between farmers and weeds that persists to this day. Recounting the history of weeds and weed control in Western Canada between 1800 and 1950 serves a number of functions. One is to provide weed scientists with some historical background and an object lesson in the consequences of seeking simple solutions to complex, long-standing problems. Another is to remind historians that we cannot truly understand the history of western settlement and agriculture without understanding the practical issues that dominated the daily lives of past generations of farmers. Yet a third function is to introduce a specific environmental history approach to Canadian historians while, at the same time, encouraging them to pay more attention to recent developments in this American-dominated field. A fourth and final reason for investigating the historical relationship between people and weeds is that it can be used to symbolize something far larger: the relationship between culture and nature in general. An exploration of this issue is made possible by the curious relationship between people and weeds, a relationship summed up by the thesis that weeds are both the the products of and participants in culture. The dissertation concludes with a discussion of recent trends in weed science and, in particular, of the merits of the "new" doctrine of weed management. Canadian historians are lectured on the danger of ignoring nature when writing about history and readers are asked to consider what the terms "nature" and "culture" mean. Do they represent discrete subjects, separate spheres of existence, a dichotomy? Or, are they just different aspects of a larger, more complex whole?

The main objective of this study was to examine the effects of intraspecific competition on the growth and reproduction of yellow nutsedge. A field experiment was conducted to examine twelve tuber densities of yellow nutsedge, ranging from 1 to 1000 tubers/m$ sp2$. Results indicate that spring tuber populations of 100 tubers/m$ sp2$ and lower require close to 100% control of the infestation in order to prevent the yellow nutsedge population from increasing. Yellow nutsedge spring tuber population does not appear to influence tuber distribution in the soil profile. All tuber densities examined produced the greatest proportion of tubers in the top 20 cm of the soil profile. Tuber and shoot production increased as initial yellow nutsedge tuber populations increased from 1 to 1000 tubers/m$ sp2$, as did tuber and shoot biomass. Consequently, intraspecific competition does not appear to come into effect at tuber populations of 1000 tubers/m$ sp2$ and less. / Predictions were made to determine the spread of yellow nutsedge based on an infestation of a single tuber. A single yellow nutsedge tuber could grow to infest an area of 50 m$ sp2$ in 5 years. Information concerning the effect of spring tuber density on the reproduction and spread of yellow nutsedge should be used in formulating control strategies for this weed.

Graduation date: 1977

Graduation date: 1982

Thesis (Ph. D.)--University of Adelaide, 1986. / Offprints of the author's articles inserted. Includes bibliographical references (v. 2, leaves 106-111).

Thesis (M. App. Sc.)--University of Adelaide, Dept. of Agronomy and Farming Systems, 1998? / Includes bibliographical references (leaves 82-89).

Thesis (Ph.D.) University of Adelaide, Dept. of Agronomy. 1989.