1. Coppice Short-Rotation Woody Crops Production Systems Introduction Advantages of Using Woody Crops for Bioenergy Energy Conversion of Woody Biomass Provide diversity of feedstocks Location and geographic distributive advantages Adaptability of species to regional areas Lower ash content Year-round availability Stable, consistent feedstock supply High density products Easy to store Easy to handle Mix with the other woody feedstocks Protect soil, water and air quality Sustainable production systems Sequester carbon Create wildlife habitat Increase diversity  landscape  biological  soil microbial and mesofauna Improve productivity of marginal farmland Combustion boilers Gasification  Synthesis gas: 20% H2, 20% C0, 5% CH3 Pyrolysis: Bio-oil & Char  Bio-Oil is a crude containing high value chemicals Biofuels Biochemical processes requiring:  Cellulosic enzymes  Distillation energy Thermochemical process  Catalytic conversion of synthesis gas  Alcohols and diesel Table 1.Summary of practitioner survey of potential for woody energy crop species for southeastern US. Southern Pines Hardwoods Coppice Southern Pines Hardwoods Coppice Elite genetic selections Adapted to wide range of sites Variety of selective herbicides Developed operations Elite genetic selections Adapted to wide range of sites Variety of selective herbicides Developed operations Vegetative propagation High density planting (6000 trees/acre) Cut every 3 to 4 years Replanting required after 25 years Efficient harvesting equipment Woody Bioenergy Crops for the Southeastern United States Mark Coleman 1 and Keith Kline 2 1 USDA-Forest Service, 241 Gateway Drive, Aiken, SC 29803; coleman.m@earthlink.net 2 Oak Ridge National Lab, Oak Ridge, TN 37831-6038; klinekl@ornl.gov Positive Response to culture treatments HerbicidesFertilization Enhanced Pine Production Potential Biomass is an important alternative energy resource that can offset greenhouse gas emissions from fossil fuels, provide crop options for marginal farmlands and improve rural economies. Forests cover nearly 60% of the southeastern US. Woody energy crops include fast growing native species that have shown large productivity gains from improved genetic resources and cultural practices. Woody feedstocks offer many advantages compared to other types of biomass and options for conversion to various types of energy (liquid fuels, electric power, and other bio-products) are possible. Here we summarize accumulated learning from southeastern practitioners’ experiences with woody cropping systems and discuss examples of many of the most promising woody energy crop species. Relatively low input crops Genomic Resources Multiple market options Environmental Benefits Process Benefits Pine Poplar, Eucalyptus, Sycamore, Sweetgum Large growth potential Forest operations equipment Genomic resources Poplar, Eucalyptus, Sycamore, Sweetgum Large growth potential Forest operations equipment Genomic resources Orlando, FL 2 ½-year-old Eucalyptus Grandis Growth Rates of 2 to 3” diameter/year 7.2 dry tons/acre/year Bainbridge, GA 4.5-year-old survived > 150 freezing nights 1.7 – 2.7 diameter per year 7 dry tons/acre/year E. amplifolia E. viminalis E. nova-anglica E. macarthurii E. camphora E. amplifolia E. viminalis E. nova-anglica E. macarthurii E. camphora Hardwood Eucalyptus Conclusions Several woody crops offer high growth potential in the southeastern US under proper silviculture but costs for hardwood plantations may be prohibitive. Loblolly pine has the most developed infrastructure. It can be grown at lower cost and at higher rates on the largest variety of sites. Bottomland hardwoods such as cottonwood and sycamore are limited by site and soil requirements and disease. Eucalyptus out performs other species in biomass output/year but is limited by frost to Florida and a narrow band along the gulf coast. Coppice crops offer potential to rapidly expand production but require research to identify the best species and cultivars for a given locale and to develop appropriate cultural practices and operational equipment. Extensive natural hardwood and mixed forest resources in the southeast also merit further study for potential contributions to bioenergy. Practitioners Survey Woody PlantationExpected ProductionProduction Crop(dry Mg/hectare-yr)Costs AdvantagesDisadvantages Low Avg. High ($dry/Mg) Cottonwood and691215-95 Broad genetic resources Narrow site requirements Hybrid Poplars Disease susceptible Sycamore7 91115-95 Rapid early growth Narrow site requirements Disease susceptible Sweetgum4 6 815-65 Broad site requirement Relatively slow growth Disease resistance Eucalyptus 18222515-65 Broad site requirement Restricted by frost High growth Hybrid Aspen91012no data Broad site requirement Undeveloped genetic material Loblolly Pine8 91010-40 Operational infrastructure Broad genetic resources Willow Cuttings for planting Cuttings for planting Harvester After cut Numerous forestry practitioners were interviewed about the potential for woody energy crops in the southeastern US. In total, over 250 person-years of southeastern forestry research experience. Each was asked to name potential crop species, management requirements, expected productivity rates and factors impacting yields. The table summarizes results. Eucalyptus Range Sycamore Experience to date has been with northern temperate culture Willow native to southern US, merits research Sycamore coppice yields twice that of seedlings Year 3 Late in year 2 Pine & Sweetgum trials - year 12 Sampling soil - sweetgum