Date of Award
Fall 12-15-2023
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Biology
First Advisor
Dr. Neil Snow
Second Advisor
Dr. Andrew George
Third Advisor
Dr. Catherine Hooey
Keywords
chestnut blight, chestnut, ecology, species distribution model, Ozarks, Ozark chinquapin reproduction
Abstract
The Ozark chinquapin, Castanea ozarkensis Ashe, is a chestnut tree with a range concentrated in the Interior Highlands of North America. Like other North American members of Castanea, it was reduced from an overstory tree to an understory shrub by the invasive chestnut blight fungus (Cryphonectria parasitica [Murrill] M.E. Barr) during the early 20th century. However, relatively little is known about the habitat of this species or its health and reproductive capability post chestnut blight. Chapter one of this study analyzed the habitat of this species through a random forest species distribution model (SDM) to predict where it might grow. Based on the values of the Area Under the Curve and other statistics, this model predicted the species’ current distribution in the study area reasonably accurately. The results of the SDM showed that elevation and slope are the most important habitat variables for the Ozark chinquapin. Additionally, the associated flora is indicative of dry, acidic, chert woodlands. This SDM and future habitat studies will enable resource agencies to narrow their survey areas and inform where Ozark chinquapins might be reintroduced as chestnut blight resistant technology develops. In Chapter II, we evaluated the health and reproductive status of the Ozark chinquapin at Roaring River State Park, approximately seventy years after the arrival of the blight to the central United States. While numerous studies have documented the response of the American chestnut (C. dentata) to chestnut blight, little is known about the health and reproductive status of the Ozark chinquapin post-blight. This study aimed to assess the factors that influence the probability of chestnut blight infection and to evaluate which variables predict reproduction in an Ozark chinquapin population in the southcentral Missouri Ozarks. We used generalized linear models and AIC model selection to examine potential factors that affect probability of reproduction or blight infection. Models showed that Ozark chinquapin reproduction was related to the maximum stem height of the tree and past fire frequency. Additionally, stem height, the presence of deer damage, and the amount of time since the area was last burned increased blight infection. Our findings suggest that the Ozark chinquapin is capable of reproduction in certain situations but is susceptible to chestnut blight through deer damage and the burn time interval, opening the door to further research to better inform conservation efforts for this blight-stricken tree.
Recommended Citation
Evilsizor, Danielle, "HABITAT AND DEMOGRAPHY OF THE OZARK CHINQUAPIN (CASTANEA OZARKENSIS) AT ROARING RIVER STATE PARK IN BARRY COUNTY, MISSOURI" (2023). Electronic Theses & Dissertations. 469.
https://digitalcommons.pittstate.edu/etd/469
