Steve McKeand
Professor Emeritus
Bio
Education
B.S. Purdue University (Forest Production) (1976)
M.S. Purdue University (Forest Genetics) (1978)
Ph.D. North Carolina State University (Forest Genetics) (1983)
Research Interests
Support of the breeding program of the Tree Improvement Program, with primary responsibility in the breeding, testing, and selection phases of the program. Specific research interests include: genetic effects on nutritional and ecophysiological processes in forest trees, genetic and environmental control of wood properties, biotechnology/breeding interface, propagation effects on forest trees, seed orchard management, and genotype by environment interactions.
Courses
FOR 725 – Forest Genetics (formerly FOR 611)
FOR 727 – Tree Improvement Research Techniques
FOR 411 – Forest Tree Genetics and Biology
Area(s) of Expertise
Forestry, Forest Genetics
Publications
- Stem Defect Rates and Ice Storm Damage for Families of Pinus taeda from Coastal and Piedmont Provenances Planted on a North Carolina Piedmont Site , FOREST SCIENCE (2024)
- Performance Based on Measurements from Individual-Tree Progeny Tests Strongly Predicts Early Stand Yield in Loblolly Pine , FOREST SCIENCE (2023)
- Long-term evaluation of intra- and inter-provenance hybrids of loblolly pine in the Piedmont region of the southeastern United States , FOREST ECOLOGY AND MANAGEMENT (2022)
- Pollination Bag Type Affects Ovule Development and Seed Yields in Pinus taeda L. , FOREST SCIENCE (2022)
- Genetic Variation and the Effect of Herbicide and Fertilization Treatments on Wood Quality Traits in Loblolly Pine , FOREST SCIENCE (2021)
- Provenance and Family Variation in Biomass Potential of Loblolly Pine in the Piedmont of North Carolina , FOREST SCIENCE (2021)
- Economic Significance of Continued Improvement of Loblolly Pine Genetics and Its Efficient Deployment to Landowners in the Southern United States , Journal of Forestry (2020)
- Genetic Parameters and Genotype-by-Environment Interactions in Regional Progeny Tests of Pinus taeda L. in the Southern USA , FOREST SCIENCE (2020)
- Modeling Self-Thinning Patterns in Loblolly Pine with Provenance and Family Effects , FOREST SCIENCE (2020)
- Pollination Bag Type Has a Significant Impact on Cone Survival in Mass Production of Controlled Pollinated Seeds in Loblolly Pine , Forest Science (2020)
Grants
Loblolly pine is the most abundant commercially grown tree species in North Carolina with over 100,000 acres of pine plantations established each year in the state. In addition to the conventional forest products industry, loblolly pine serves as a promising source for renewable energy in the form of woody biomass. Large genetic differences exist for growth, disease resistance, and stem form. By planting genetically superior trees with desirable traits, it may be possible to substantially increase the amount and quality of biomass produced at a given site. The goal of this project is to evaluate different planting stock (families) in combination with different thinning regimes in order to inform forest landowners how best to maximize their returns when supplying both the bioenergy and sawtimber markets. This project was initiated in 2012, with the planting of a high spacing density (1037 trees/acre) long-term field trial in the NC Piedmont. The trial includes 10 of the best Coastal and 10 of the best Piedmont families with varying degrees of adaptation, growth, and wood characteristics. Different thinning regimes will be explored using eight year measurements, and the predicted financial returns from the thinnings as well as projected sawtimber production will be evaluated.
Loblolly pine (Pinus taeda L.) is the primary woody bioenergy feedstock for North Carolina. There are over 2.6 million acres of pine plantations in NC, and almost all have been established with loblolly pine genotypes from the NCSU Cooperative Tree Improvement Program. The 5-year-old Loblolly Pine Biomass Genetics/Cropping Study at the NCDA&CS Umstead Farm at Butner, NC is a unique field laboratory where we are evaluating the genetic differences in traits that impact biomass/bioenergy traits. In this field trial, we planted 10 of the best Coastal and 10 of the best Piedmont loblolly pine varieties with varying degrees of adaptation, growth, and wood characteristics. At age 3 years, Coastal families grew faster but suffered more cold damage and stem malformations than the better adapted Piedmont families. Funding is sought to continue this critical experiment and to better understand the genetic basis of variation in biomass/biofuel traits and improve pine varieties for biomass production. Trees will be at the ideal age to collect wood samples and measure density, strength, and moisture content to project dry weight yields and biomass/bioenergy value.
The goal for this partnership is to plant, develop and document the information and tools needed to demonstrate the sustainable production of biomass for bioenergy across the Southern US. Specifically, this program will develop and demonstrate sustainable, flexible, integrated biomass production solutions that create innovative deployment scenarios to reliably produce and supply biomass feedstocks that are optimized for performance in leading conversion technologies. Research and development activities will target specific barriers in each step of the supply chain that are identified as critical to regional economic and/or environmental sustainability. Education, extension and outreach activities will be integrated so that the results of this work will reach target audiences with appropriate real-world examples.
Pine plantation forestry in the southeastern US is an important part of the regional economy, as well as the regional carbon budget. Climate changes over the coming decades have the potential to affect the productivity and carbon-cycling functions of these plantations. This research proposal is a combined effort by forestry researchers from several disciplines to conduct trans-disciplinary research, integrate analysis of data, provide an information base and generate a set of tools that will be useful to land owners and managers in the region. The project will also educate the next generation of forest scientists to address the challenges facing the southeastern US forestry sector, and transfer technology to the private sector to assist with rural economic development.
Loblolly pine (Pinus taeda L.) can be a major bioenergy feedstock for North Carolina, because over 100,000 acres of pine plantations are established each year in the state. In the NCSU Cooperative Tree Improvement Program, substantial genetic differences exist in loblolly pine for growth, disease resistance, and stem form. Such variation provides an opportunity to dramatically increase the amount and quality of biomass produced by planting varieties with desirable biomass/bioenergy traits and developing optimal plantation management regimes. In January/February 2012, we established a long-term field trial at the NC Department of Agriculture Umstead Farm at Butner, NC. We planted 10 of the best Coastal and 10 of the best Piedmont varieties with varying degrees of adaptation, growth, and wood characteristics. Coastal families will likely be faster growing than the Piedmont families but may be less well adapted to this Piedmont site. By planting the higher-risk Coastal material, we can evaluate the risk/reward balance of producing high-quality bioenergy feedstock. Funding is sought to obtain biometric data at years 3 and 5 and to manage this long-term experiment to its initial harvest/thinning around 2022 and final harvest around 2037.
Loblolly pine is grown across millions of acres and found on a wide range of sites in the Southeast, and may be an ideal feedstock for the developing biofuels industry because it does not compete with America?s food production. Substantial genetic differences exist in loblolly pine that will influence biomass/biofuel production. It is possible to dramatically increase the amount of biomass produced at any given site, by planting genetically superior trees with desirable biomass/biofuel traits such as fast growth, high cellulose, and low lignin. We propose testing 20 of the best pine families, with varying degrees of site adaptation and growth characteristics. Ten of the top volume families adapted to the Piedmont region as well as 10 of the top volume families from the Coastal region will be planted at the Butner field site. The Coastal families will be faster growing than the Piedmont families, but they will be less well adapted to this Piedmont site. By incorporating the higher-risk Coastal material, we will be able to evaluate the risk/reward balance of planting faster-growing material that is less adapted to the region.
The NCSU - Industry Cooperative Tree Improvement Program has access to a wide variety of progeny tests that include a range of elite loblolly pine parents in various mating designs. Sampling will be done in all these trials. These tests involve over 60 elite loblolly pine parents of the Atlantic Coastal Plain (ACP) breeding population mated in a partially-disconnected diallel design. Offspring of all crosses were planted in replicated field trials at five or six sites. Breeding values of parents, crosses and offspring were predicted from phenotypic data collected at age six. These trials are now 6 to 12 years old, and have reached the stage at which meaningful analysis of wood properties can be carried out. Associations found in natural populations will be tested in progeny from the second and third cycle of selection, and the effect of allelic substitutions on breeding values estimated in those test populations. The panel of 1536 SNPs will be analyzed in 40 of the parents that were tested in the elite diallel trials, plus an average of 14 progeny (randomly selected after removal of outliers) from each of about 140 crosses. A total of 2000 trees (parents and offspring) will be genotyped at UC Davis for the panel of 1536 SNPs. Increment cores will be collected from the progeny individuals for analysis of wood properties using established methods, and breeding values (BVs) calculated for the parent trees based on the phenotypes of their progeny. Growth, disease incidence, stem quality, and crown trait data already exist for these populations and will be subjected to association testing along with wood properties. This will permit inference of a SNP breeding value (SNP-BV) for each of the selected parents, based on how many of the beneficial SNPs it has. Correlations between those SNP-BVs and the real BVs based on phenotypic values of measured progeny will be examined. Based on results of the association tests noted above, specific hypotheses on allelic substitution (additive genetic effect) or allelic interaction (epistatic effect) will be tested by examining genotypes of parents from a different set of diallel progeny tests that have already been analyzed for wood property phenotypes. The parent BVs for wood properties can be calculated from the known progeny phenotypes, and determination of parental SNP genotypes will provide a second validation of the association between particular SNPs and specific phenotypes in the NCSU breeding populations. Additive and epistatic effects can be examined in this independent population as well, along with potential environmental interactions. These tests are planted at sites across the southern US, from South Carolina to Mississippi, and sample a much greater fraction of the total commercial land base planted to loblolly pine. For application to tree breeding, it is important to identify those SNPs with the largest and most consistent effects on phenotype across different genetic backgrounds and different environments, and then identify multiple elite parents that carry those SNPs for use in future breeding efforts.
This project will test the economic impacts on ethanol production of variation in chemical and physical properties of pine wood. We will compare acid, alkaline, and solvent pretreatments on samples of wood with different properties, and determine the yields of fermentable sugars. These yields will be used in economic modeling to project cost-efficiency of ethanol production from pine biomass of different types. The economic model will also include estimates of the capital costs of building an ethanol production facility to utilize pine biomass, and the raw material and process costs of ethanol production from pine biomass. The results will be compared with similar analyses for poplar feedstock, based on existing data, to determine economic feasibility of ethanol production from pine biomass feedstocks. The results of this project will guide investors, researchers, and economic analysts interested in the cost-efficiency of pine biomass feedstocks for ethanol production in North Carolina.
The NCSU - Industry Cooperative Tree Improvement Program has access to a wide variety of progeny tests that include a range of elite loblolly pine parents in various mating designs. Sampling will be done in all these trials. These tests involve over 60 elite loblolly pine parents of the Atlantic Coastal Plain (ACP) breeding population mated in a partially-disconnected diallel design. Offspring of all crosses were planted in replicated field trials at five or six sites. Breeding values of parents, crosses and offspring were predicted from phenotypic data collected at age six. These trials are now 6 to 12 years old, and have reached the stage at which meaningful analysis of wood properties can be carried out. Associations found in natural populations will be tested in progeny from the second and third cycle of selection, and the effect of allelic substitutions on breeding values estimated in those test populations. The panel of SNPs will be analyzed in 40 of the parents that were tested in the elite diallel trials, plus an average of 14 progeny (randomly selected after removal of outliers) from each of about 140 crosses. A total of 2000 trees (parents and offspring) will be genotyped at UC Davis for the panel of SNPs. Increment cores will be collected from the progeny individuals for analysis of wood properties using established methods, and breeding values (BVs) calculated for the parent trees based on the phenotypes of their progeny. Growth, disease incidence, stem quality, and crown trait data already exist for these populations and will be subjected to association testing along with wood properties. This will permit inference of a SNP breeding value (SNP-BV) for each of the selected parents, based on how many of the beneficial SNPs it has. Correlations between those SNP-BVs and the real BVs based on phenotypic values of measured progeny will be examined. Based on results of the association tests noted above, specific hypotheses on allelic substitution (additive genetic effect) or allelic interaction (epistatic effect) will be tested by examining genotypes of parents from a different set of diallel progeny tests that have already been analyzed for wood property phenotypes. The parent BVs for wood properties can be calculated from the known progeny phenotypes, and determination of parental SNP genotypes will provide a second validation of the association between particular SNPs and specific phenotypes in the NCSU breeding populations. Additive and epistatic effects can be examined in this independent population as well, along with potential environmental interactions. These tests are planted at sites across the southern US, from South Carolina to Mississippi, and sample a much greater fraction of the total commercial land base planted to loblolly pine. For application to tree breeding, it is important to identify those SNPs with the largest and most consistent effects on phenotype across different genetic backgrounds and different environments, and then identify multiple elite parents that carry those SNPs for use in future breeding efforts.
The longleaf pine cone crop in 2009 was good throughout much of the South and was excellent in some areas such as the Carolina Sandhills. Unfortunately, relatively little is known about the genetic quality of much of the seed collected from seed orchards and seed production areas in many regions. Orchards in the Carolinas, Georgia, Alabama, and Mississippi have never been as well tested as seed orchards in Florida, the Lower Gulf Coastal, and the Western Gulf Coastal regions. For example, in the NC State Cooperative Tree Improvement Program, most of the 8+/- seed orchards established 30+ years ago were never tested or were very poorly tested. The same is true for some orchards established by the USDA Forest Service. With the current effort to establish 300,000 acres of new longleaf plantations annually, there is an urgent need to use the best genetic sources of longleaf pine available for the multitude of objectives that landowners and/or government agencies might have. The select trees established in these orchards were chosen for superior growth and stem form from natural stands. Although the gains in the performance of the progeny from these orchard trees compared to progeny from trees in natural stands are likely to be modest, there will be some selections that have superior attributes for many different traits. Some landowners might be interested in timber production or pine straw production, and there will be significant genetic variation for traits affecting these management objectives. Disease resistance (fusiform rust, pitch canker, and brown spot) will likely be under moderate to strong genetic control as well. Even wood properties that might be beneficial for nesting red cockaded woodpeckers are known to be under very high genetic control. One thing is for certain, not all longleaf pines were created equal. Some will be better than others for almost any trait that a forester or landowner or government agency can conceive. Through progeny testing, we can assess the genetic variation for many desirable traits, and landowners can decide which seedlots with what desirable attributes should be deployed. Testing Plans: From the 2009 seed harvest, we have approximately 150 seedlots to test. Seeds came primarily from parent trees in seed orchards, but about 20 seedlots are bulk collections from natural stands. These seedlots come from Virginia to Louisiana and Mississippi. Our plans are to grow containerized seedlings in Raleigh and establish in 10 genetic trials throughout the Southeast in 2010 and 2011