Department of Forestry University of Kentucky John M. Lhotka (University of Kentucky) John M. Lhotka Wood Energy Harvesting and Woodlands Costs and Benefits for Woodland Owners Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Potential Demand for Biomass in Kentucky 25 million tons of biomass per year by 2025 Unintended Consequences of Biomass Harvesting Source: Final Report, Kentucky Executive Task Force on Biofuels and Biomass

John M. Lhotka (University of Kentucky) Meeting Potential Future Demand 25 million tons per year biomass production could involve land use changes of approximately 2 million acres (15% of Kentucky’s farmland) Potential sources: Unintended Consequences of Biomass Harvesting Source: Final Report, Kentucky Executive Task Force on Biofuels and Biomass

John M. Lhotka (University of Kentucky) Meeting Potential Future Demand What will be the impact of wood energy markets on forest resources in Kentucky and the surrounding Central Hardwood Region? Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest Practices in the Central Hardwood Region Traditionally, harvests have been stem-only removals of commercial sawlogs Unintended Consequences of Biomass Harvesting

sawtimber veneer stave tie cant Source: Jeff Stringer

John M. Lhotka (University of Kentucky) Wood Energy and Shifts in Forest Practices Wood energy markets in Kentucky would: –Create economic incentive for utilization of small diameter trees and woody residues –Likely increase the amount of material removed in forest harvests Unintended Consequences of Biomass Harvesting

sawtimber veneer stave tie cant pulpwood residual Source: Jeff Stringer

John M. Lhotka (University of Kentucky) Forest Practices in the Central Hardwood Region Sawlog harvests typically use cut-to-length logging due to high economic efficiency of removing large diameter material Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Wood Energy and Shifts in Forest Practices Mechanized whole-tree harvesting is generally preferred for removal of small trees in hardwood stands Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Cut-to-length vs. whole-tree removals Compared to cut-to-length harvests, fully mechanized whole-tree harvesting has greater potential to: –Modify nutrient cycling and reduce site nutrient capital –Increase soil disturbance and compaction –Alter regeneration processes Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Wood Energy and Shifts in Forest Practices Summarizing Potential Shifts –Material Utilized Sawlogs → Sawlogs + Small Stem Wood + Branches –Removal Method Cut-to-length → Mechanized whole-tree harvesting Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Wood Energy and Shifts in Forest Practices So what will be the combined effects of increased removal and a shift in harvest disturbance type on forest processes? Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Potential Effects of Wood Energy Harvesting Soils and site productivity Hydrology Forest dynamics and species composition Biodiversity and wildlife habitat Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Soils Disturbance and Harvest Methods Effects of forest harvesting on soils –Displacement and erosion –Compaction (increased bulk density) Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Soils Disturbance and Harvest Methods Effects of forest harvesting on soils –Displacement and erosion –Compaction (increased bulk density) Impact level linked to machine traffic Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Soils Disturbance and Harvest Methods Effects of forest harvesting on soils –Displacement and erosion –Compaction (increased bulk density) Impact level linked to machine traffic –Degree of mechanization –Harvest intensity –Movement patterns Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Soils Disturbance and Harvest Methods Biomass harvesting –Increased mechanization and wood removal Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Soils Disturbance and Harvest Methods Biomass harvesting –Increased mechanization and wood removal Potential impacts: –Higher mineral soil exposure –Damage to forest regeneration –Compaction and tree growth Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Soil productivity linked with site nutrient capital and organic matter pools Nutrient content of trees higher in foliage and branches than in tree boles Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Soil productivity linked with site nutrient capital and organic matter pools Nutrient content of trees higher in foliage and branches than in tree boles Tree removals associated with a biomass market could potentially –Increase nutrient loss –Decrease site organic matter Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Does whole-tree harvesting degrade long-term productivity? Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Does whole-tree harvesting degrade long-term productivity? –Research is not conclusive, but generally suggests impacts are minimal under historic rotation lengths Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Does whole-tree harvesting degrade long-term productivity? –Research is not conclusive, but generally suggests impacts are minimal under historic rotation lengths How much material has to be removed before site productivity declines? Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Removal and Long-term Productivity Does whole-tree harvesting degrade long-term productivity? –Research is not conclusive, but generally suggests impacts are minimal under historic rotation lengths How much material has to be removed before site productivity declines? –No definitive research in the Central Hardwood Region exists to define the tipping point Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Hydrology Increased streamflow due to intensive vegetation removal Increase streamflow and effects on water quality –Sedimentation –Nutrient export Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest dynamics Regeneration establishment and dynamics linked to post-harvest microenvironment Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest dynamics Regeneration establishment and dynamics linked to post-harvest microenvironment Increased harvest disturbance yields increased: –Damage to residual vegetation –Mineral soil exposure Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest dynamics Regeneration establishment and dynamics linked to post-harvest microenvironment Increased harvest disturbance yields increased: –Damage to residual vegetation –Mineral soil exposure Potential Impacts Promote regeneration of species that reproduce from seed at the time of harvest Loss of advance reproduction pools of important species such as oaks Provides opportunities for invasive plants Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest dynamics Increased disturbance intensity linked with mechanized biomass utilization could –Amplify oak regeneration problems –Facilitate the expansion of the established invasive plant populations Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Forest dynamics Increased disturbance intensity linked with mechanized biomass utilization could –Amplify oak regeneration problems –Facilitate the expansion of the established invasive plant populations Species compositional shifts would impact biodiversity and have economic ramifications for the region Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Whole Tree Removal Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Tree Top Retention Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Biodiversity and wildlife habitat Habitat changes associated with biomass harvesting could negatively affect species requiring: –intact forests (e.g., interior bird species) –sheltered and shaded environments (e.g., salamanders, understory wildflowers) Displacement of native species by invasive species Increases in species that favor drier habitats and those requiring open forests with young age classes Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Mitigation Approaches Best Management Practices (BMPs) for wood energy harvesting Current implementation by state governments –Pennsylvania, Maine, Minnesota, Missouri, Wisconsin –Kentucky is developing biomass BMP recommendations Unintended Consequences of Biomass Harvesting

John M. Lhotka (University of Kentucky) Potential Benefits of Wood Energy Markets Unintended Consequences of Biomass Harvesting Wood energy markets can help landowners by facilitating practices that: Enhance woodland health Improvement stand quality and growth Promote regeneration of desired species Maximize revenue Reduce wildfire risk Aesthetics

John M. Lhotka (University of Kentucky) Examples: Potential Benefits Unintended Consequences of Biomass Harvesting Improve dense, poor quality stands Remove low-grade trees

John M. Lhotka (University of Kentucky) Examples: Potential Benefits Unintended Consequences of Biomass Harvesting Reduce fuels and wildfire risk Ability to sell low grade and damaged trees

John M. Lhotka (University of Kentucky) How Can Wood Energy Harvests Help? Unintended Consequences of Biomass Harvesting Offset costs of beneficial management activities throughout the life of a stand Establishment

John M. Lhotka (University of Kentucky) How Can Biomass Harvests Help? Unintended Consequences of Biomass Harvesting Benefits Reduce density Favor desired species Improve quality Enhance growth Increase yield Shorten rotation

John M. Lhotka (University of Kentucky) How Can Biomass Harvests Help? Unintended Consequences of Biomass Harvesting Benefits Improve germination, survival, and growth of desired seedlings Removal of unwanted vegetation and slash

John M. Lhotka (University of Kentucky) How Can Biomass Harvests Help? Unintended Consequences of Biomass Harvesting Benefits Create conditions require to establish new stand of desired commercial species

John M. Lhotka (University of Kentucky) Dedicated Energy Crops in Kentucky Energy crops involve a "closed-loop process" in that they grown specifically for their ability to generate energy Advantages: –Short rotation crops –Vegetative regeneration after each harvest –Allowing multiple harvests without reestablishment –Reduce harvest pressure on natural forests –Strategic establishment reduces transport costs Reclaimed surface mines as a source for sustainable bioenergy feedstock

John M. Lhotka (University of Kentucky) Dedicated Energy Crops in Kentucky Drawbacks: –Can displace food production on crop lands –Reduced biodiversity following land conversion Programs like BCAP “will not incentivize the conversion of old growth, other natural forests, or savannahs to biomass plantings”, –Non-native species –Concerns regarding reduced long-term site productivity Reclaimed surface mines as a source for sustainable bioenergy feedstock

John M. Lhotka (University of Kentucky) Reclaimed Surface Mines in Kentucky Dedicated energy crops on reclaimed surface mines in Kentucky presents an excellent opportunity –Increase biomass production –Does not divert current agricultural or naturally forested lands to plantations –Facilitate restoration and reforestation –Utilizes existing transportation infrastructure and workforce Reclaimed surface mines as a source for sustainable bioenergy feedstock

John M. Lhotka (University of Kentucky) Important Lingering Questions Timeline of developing markets Landowner attitudes towards biomass harvesting Levels of biomass removal and maintenance of site productivity and habitat Long-term regeneration dynamics following biomass harvesting Role of dedicated energy crops Unintended Consequences of Biomass Harvesting