ABSTRACT HALL, KEVIN BROWN. Modeling the Actual Productivity of Eucalyptus benthamii in the Southeastern United States. (Under the direction of Jose Stape). Eucalyptus species have been investigated as viable production forest species in the southeastern United States for more than 40 years. A frost tolerant Eucalyptus species with reduced climatic limitations would allow forest companies and landowners to plant Eucalyptus on a larger scale over a greater geographic range. Initial trials in the 1960s resulted in the establishment of Eucalyptus plantations in southern Florida with tropical species such as E.grandis, E.robusta, E.camaldulensis and E.tereticornis. Later trials in the 1970s and 1980s showed some promising growth and survival of E.viminalis, E.nova- anglica, E.macarthurii and E.camphora in states such as Georgia, Alabama and South Carolina. However, several hard, freezes in 1983 and 1984 caused severe damage to many of the trials ultimately ending these efforts. Since that time, forest companies around the world have had success with Eucalyptus in temperate and subtropical areas. As demand hardwood fiber grew, the planted area expanded into colder regions (e.g. southern region of Latin America, Europe and South Africa), resulting in breeding efforts focused on frost tolerant Eucalyptus. In recent Eucalyptus frost tolerant trials established by NCSU/ Forest Productivity Cooperative (FPC), E.benthamii has shown superior growth rates as well as frost tolerance for USDA Cold Hardness Zones 8 to 9. Also, the current research efforts of the NCSU/FPC, several US based companies have shown interested in E.benthamii as a feed stock resulting in a variety of research trials and pilot plantations across the SE US. Similarly, available plot-level data for E.benthamii are disjunct. The aggregation of these data can provide valuable information for assessing the growth of E.benthamii across the SE US. The aim of this project is to develop volumetric and biomass growth and yield models to characterize the current performance of E.benthamii in the SE US. During 2012-2013, a network of one hundred permanent inventory plots of E.benthamii ranging from ten months to 13 years in age across seven states (AL, GA, LA, SC, TX and NC) were established. These plots range in size from 100 to 400 m2 and all diameters at breast height and total stem height were measured. Site quality was established by developing a site index guide curve using age and mean dominant height. Site index with a base age of six years for E.benthamii in the SE US ranged from six to 21 meters. Functions for mean dominant height and stand basal area based on age were developed to project each stand variable through time. Yield tables for volume, green weight and biomass, in metric units, were developed by using the combined- variable of mean dominant height and stand basal area for each age class. Eucalyptus benthamii and six other cold-tolerant Eucalyptus species were measured weekly for one-year while climate data during the winter months was measured hourly. The behavior of Eucalyptus cold-tolerant species was evaluated to obtain insight on growth controls over the winter months in the SE US. Eucalyptus species have shown little lag time in expressing the fixed carbon as stem growth. Temperature is the leading climate variable that controls growth of cold-hardy Eucalyptus species. The objective of this study was to examine differences in cold tolerant Eucalyptus rate of biomass accumulation through the winter months and to develop biomass gain by species and the weekly average minimum temperature. © Copyright 2015 Kevin Brown Hall All Rights Reserved Modeling the Actual Productivity of Eucalyptus benthamii in the Southeastern United States by Kevin Brown Hall A thesis submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the degree of Master of Science Forestry and Environmental Resources Raleigh, North Carolina 2015 APPROVED BY: _______________________________ _______________________________ Jose Stape Bronson Bullock Committee Chair _______________________________ _______________________________ Douglas Frederick Jeff Wright BIOGRAPHY Kevin Brown Hall, son of Walter and Mary Kay Hall, was born in Raleigh, North Carolina on May 14, 1987. When considering an undergraduate degree focus, Kevin’s passion for outdoors and sciences drew his attention to undergraduate Forest Management program at North Carolina State University. Kevin capitalized on opportunities during his undergraduate career at NCSU to gain experience in forest plantations systems by traveling abroad to participate in undergraduate research. In 2012 immediately after completing his undergraduate degree, Kevin began graduate school at NCSU by accepting a study abroad program in Curitiba, Brazil to learn about silvicultural practices of plantation forests in southern Brazil. Kevin completed his graduate work for Master of Science in Forestry with a focus in growth and yield modeling and frost-tolerant Eucalyptus silviculture. ii ACKNOWLEDGMENTS Firstly, I would like to thank my parents, Walter and Mary Kay Hall, for their support and encouragement throughout this process. Without their guidance and support I would not be where I am today. I am very fortunate to have the support of my family and friends and their encouragement, advice and humor. I would also like to thank my committee for the guidance and support; Dr. Jose Stape, Dr. Bronson Bullock, Dr. Doug Frederick, and Dr. Jeff Wright. A special thanks to Dr. Stape for accepting me as his graduate student, encouraging me to pursue my interest in Eucalyptus through a Master’s project, and giving me the opportunity to grow as a forest professional. I would also like to acknowledge the Forest Productivity Cooperative (FPC), its members, fellow graduate students and undergraduate interns for all of their encouragement, advice, willingness to collaborate and help in achieving the goals of my Master’s thesis project. I would like to specifically acknowledge Henrique Ferraço Scolforo, Marcello Bontempi Pizzi, Caroline Rodrigues, Carolina Mata Machado and Nathan Thomas for their help with data collection in the field. Finally, I would like to acknowledge the Southeastern Partnership for Integrated Biomass Supply Systems (IBSS) and Dr. Steve Kelley for their support to realize this project. The IBSS project is supported by the Agriculture and Food Research Initiative (AFRI) Competitive Grant no. 2011-68005-30410 from the USDA National Institute of Food and Agriculture. iii TABLE OF CONTENTS LIST OF TABLES ................................................................................................................. vi LIST OF FIGURES ............................................................................................................. viii CHAPTER ONE: INDIVIDUAL STEM VOLUMETRIC, GREEN WIEGHT AND BIOMASS EQUATIONS FOR EUCALYPTUS BENTHAMII AND OTHER SPECIES WITHIN THE SECTION MAIDENARIA PLANTED IN THE SOUTHEASTERN UNITED STATES .................................................................................................................................... 1 Introduction ............................................................................................................................. 1 Eucalyptus in exotic environments ........................................................................................ 2 Eucalyptus in the United States ............................................................................................ 3 Stem allometric equations and biomass partitioning............................................................ 7 Materials and Methods ........................................................................................................... 9 Individual stem volume, green weight and biomass ........................................................... 10 Biomass partitioning of Eucalyptus benthamii ................................................................... 14 Statistical Analysis .............................................................................................................. 15 Results and Discussion .......................................................................................................... 16 Individual stem volume, green weight and biomass ........................................................... 16 Merchantable ratio of frost tolerant Eucalyptus ................................................................ 20 Biomass partitioning of Eucalyptus benthamii ................................................................... 21 Conclusion ............................................................................................................................. 24 References .............................................................................................................................. 26 CHAPTER TWO: A GROWTH AND YIELD MODEL FOR EUCALYPTUS BENTHAMII IN THE SOUTHEASTERN UNITED STATES .................................................................... 49 Introduction ........................................................................................................................... 49 Eucalyptus silviculture in the southeastern United States .................................................. 53 Developing a growth and yield model for Eucalyptus benthamii ....................................... 54 Materials and Methods ........................................................................................................