Date of Award

Fall 2013

Project Type

Thesis

Program or Major

Plant Biology

Degree Name

Master of Science

First Advisor

Kirk Broders

Abstract

Butternut (Juglans cinerea) trees are being extirpated from their natural range by means of an epidemic caused by a fungal pathogen. Widespread mortality is reminiscent of past epidemics on American chestnut (Castanea dentata) and American elm (Ulmus americana ). Understanding the course of contemporary decline of this tree species will provide greater insight on processes of potential extinction and the results of management to prevent it.

This thesis applies an interdisciplinary approach to characterize butternut of the northeastern Unites States. While there is evidence of weak genetic structuring, butternut appears to have maintained sufficient dispersal to prevent isolation and inbreeding depression. This observed genetic variation is an artifact of past community contiguity. Today, butternuts are recruiting insufficiently to prevent near-term population collapse. Integration of resistant hybrids should be a top priority. Information related in this thesis illuminates voids in our understanding of butternut and should be used to guide conservation policy.

Share

COinS