Mathematics, Department of


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A DISSERTATION Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy, Major: Mathematics, Under the Supervision of Professors Richard Rebarber and Brigitte Tenhumberg. Lincoln, Nebraska: August, 2016

Copyright (c) 2016 Christina J. Edholm


In my dissertation I will discuss the use of optimal control theory to determine management strategies for an invasive species. I focus on a Diaprepes Root Weevil, which is an invasive species having a substantial negative impact on citrus tree growth in regions such as Florida and California. At the larva stage of the life cycle Diaprepes Root Weevils cause destruction of citrus trees at the root level resulting in loss of citrus crops. This detrimental effect for farmers motivates research into how to minimize the economic loss due to the Diaprepes Root Weevil. For my work, I use optimal control theory to determine levels of pesticide or biological control to apply to the Diaprepes Root Weevil to reduce the economic loss.

Advisers: Richard Rebarber and Brigitte Tenhumberg