Adaptive Forest Management

A procedural approach to management developed to enable forest managers to improve the effectiveness of their management systems through formal commitment to performance evaluation procedures; includes planning, implementation, monitoring, evaluation, response, and reporting steps.

Adaptive Management

A dynamic approach to forest management in which the effects of treatments and decisions are continually monitored and used, along with research results, to modify management on a continuing basis to ensure that objectives are being met.

Anaerobic Digestion

Decomposition of biological wastes by micro-organisms, usually under wet conditions, in the absence of air (oxygen), to produce a gas comprising mostly methane and carbon dioxide.

Annual Removals

The net volume of growing stock trees removed from the inventory during a specified year by harvesting, cultural operations such as timber stand improvement, or land clearing.

Ash

The noncombustible components of fuel.

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Barrel of Oil Equivalent (BOE)

The amount of energy contained in a barrel of crude oil, i.e. approximately 6.1 GJ (5.8 million Btu), equivalent to 1,700 kWh. A "petroleum barrel" is a liquid measure equal to 42 U.S. gallons (35 Imperial gallons or 159 liters); about 7.2 barrels are equivalent to one tonne of oil (metric).

Best Management Practices

Management guidelines formulated by each state to enable forest managers to maintain and improve the environmental values of forests associated with soils, water, and biological diversity; primarily used for the protection of water quality.

Bio-based Products

Aproductdetermined by the U.S. Secretary of Agriculture to be a commercial or industrial product, other than food or feed, that is composed in whole or in significant part, of biological products or renewable domestic agricultural materials including plant, animal, marine materials, or forestry materials.

Biochemical Conversion

The use of fermentation or anaerobic digestion to produce fuels and chemicals from organic sources.

Biodiversity

Diversity of species, genes, ecosystem function, and habitats.

Bioenergy

Renewable energy produced from organic matter through the conversion of complex carbohydrates. This energy may either be used directly as fuel, processed into liquids or gasses, or be a residual of the processingor conversion mechanisms.

Biofuels

Fuels made from biomass resources, or their processing and conversion derivatives. Biofuels include ethanol, biodiesel, and methanol.

Biogas

A gas produced from biomass, usually combustible.

Biomass

Biomass isany organic matter including forest and mill residues, agricultural crops and wastes, wood and wood wastes, animal wastes, livestock operation residues, aquatic plants, and municipal and industrial wastes.

Biorefinery

A facility that processes and converts biomass into value-added products. These products can range from biomaterials to fuels such as ethanol or important feedstocks for the production of chemicals and other materials. Biorefineries can be based on a number of processing platforms using mechanical, thermal, chemical, and biochemical processes.

Biosolids

Solids removed from wastewater during the treatment process; can be used as fertilizer.

Black Liquor

Solution of lignin-residue and the pulping chemicals used to extract lignin during the manufacture of paper.

Bottom Ash

Ash that collects under the grates of a combustion furnace.

British Thermal Unit

A non-metric unit of heat, still widely used by engineers. One Btu is the heat energy needed to raise the temperature of one pound of water from 60°F to 61°F at one atmosphere pressure. 1 Btu = 1055 joules (1.055 kJ).

Bundlers

A machine that collects, compresses, and binds forest residues in cylindrical bundles.

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Calorific Value

The maximum amount of energy that is available from burning a substance.

Carbon Cycle

The process of transporting and transforming carbon througout the natural life cycle of a tree from the removal of carbon dioxide from the atmosphere to the accumulation of carbon in the tree as it grows, and the release of carbon dioxide back into the atmosphere when the tree naturally decays or is burned.

Carbon Displacement

Offsetting of CO₂ emissions from fossil fuel combustion by substituting fossil fuels with bioenergy.

Carbon Sequestration

The provision of long-term storage of carbon in the terrestrial biosphere, underground, or oceans, so that the buildup of carbon dioxide, a principle greenhouse gas, concentration in the atmosphere reduces or slows.

Cellulose

A straight-chain polymer built up of a large number of glucose anhydride molecules with the empirical formula off (C6H10O5)n and is the principle chemical constituent of the cell secondary walls of higher plants and occurs mainly as long, hollow, chains called fibers.

Char

The remains of solid biomass that has been incompletely combusted, such as charcoal if wood is incompletely burned.

Chipper

A large mechanized device that reduces logs, whole trees, slab wood, or lumber to chips of more or less uniform size. Stationary chippers are used in sawmills, while trailer-mounted whole-tree chippers are used in the woods.

Chip Van

Vans are enclosed box trailers, generally8 to8.5 ft in width, designed to be less than12.50 ft high when pulled by a road tractor. The difference between the box trailers seen on most highways and vans hauling harvesting products (bulk vans) is that most box trailers are built for containerized cargo (commodities in boxes or on pallets).

Clean Chips

Chipped wood free of bark, needles, leaves, and soil contamination.

Cleaning

Release treatment made in forest stand in which the vegetation size is not past the sapling to free the favored trees from less desirable individuals that overtop them or are likely to do so.

Clearcutting

Regeneration or harvesting method that removes essentially all woody vegetation which will compete with the desired crop trees in one harvesting operations.

Cofiring

Utilization of bioenergy feedstocks as a supplementary energy source in high efficiency boilers.

Cogeneration

The sequential production of electricity and useful thermal energy from a common fuel source.Heat from this industrial process can be used to power an electric generator,used for industrial processes, or space and water heating purposes.

Combustion

Burning. The transformation of biomass fuel into heat, chemicals, and gases through chemical combination of hydrogen and carbon in the fuel with oxygen in the air.

Combustion Efficiency

The effeciency of converting available chemical energy in the fuel to heat.

Comminuted Material

Biomass material that has been pulverized or precision reduced somehow into smaller sized material.

Composite Residue Log

Compacted logging residues into cylindrical bales or bundles.

Container Trailer

A trailer designed to hold bulk material and the container is designed to be handled full. Because of this, they are built with sturdy walls and supports and their total capacity in cubic volume is less than bulk vans or log trailers. However, they can be left on a site and filled as desired, and then removed and replaced with an empty container at the same time.

Crown Thinning

Removal of trees from the upper level in the canopy in order to favor desired crop trees whose crowns are at a lower position in the canopy.

Cut-to-Length

Trees are felled, delimbed, and bucked to various assortments or dimensions. directly in the stump area.

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Deadwood

Dead standing or fallen woody biomass from woody trees or shrubs resulting from various events that may have killed the plant in natural or managed forests, including old age, fire, disease, and logging.

Digester

An airtight vessel or enclosure in which bacteria decomposes biomass in water to produce gas.

Direct Impacts

The set of expenditures applied to the predictive model for impact analysis in input-output modeling.

Dirty Chips

Chipped wood containing bark, needles, leaves, and soil.

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Effluent

The liquid or gas discharged from a process or chemical reactor, usually containing residues from that process.

Energy Ratio

The energy ratio of a bio-energy production chain is expressed as the ratio of the energy output versus the energy input, compared to the conventional fuel lifecycle. An energy ratio below one suggests energy input is higher than energy output.

Even-aged Management

Management technique for a stand of trees composed of a single age class.

Extinction

The loss of an animal or plant species from the world.

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Feedstock

Raw material used for the generation of bioenergy and the creation of other bioproducts.

Fermentation

Conversion of carbon-containing compounds by micro-organisms for production of fuels and chemicals such as alcohols, acids or energy-rich gases.

Flail Delimber

A machine used for delimbing multiple elongated tree stems. It includes a pair of vertically mounted, longitudinally offset flail members with flexible impact members mounted on rotatable drums.

Fly Ash

Ash transported through the combustion chamber by the exhaust gases and generally deposited in the boiler heat exchanger.

Fossil Fuel

Solid, liquid, or gaseous fuels formed in the ground after millions of years by chemical and physical changes in plant and animal residues under high temperature and pressure. Oil, natural gas, and coal are fossil fuels.

Forwarder

A vehicle that carries logs completely off the ground from stump to road side landing.

Fuel Cell

A device that converts the energy of a fuel directly to electricity and heat, without combustion.

Fuel Treatment Thinnings

Trees removed from the forest for the sole purpose of reducing the risk of wildfires.

Full Cost Method

Cost accounting method that allocates the total production cost across biomass and conventional wood products.

Furnace

An enclosed chamber or container used to burn biomass in a controlled manner to produce heat for space or process heating.

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Gas Turbine

A turbine that converts the energy of hot compressed gases, produced by burning fuel in compressed air into mechanical power. Often fired by natural gas or fuel oil.

Gasification

A chemical or heat process to convert a solid fuel to a gaseous form.

Gasifier

A device for converting solid fuel into gaseous fuel. In biomass systems, the process is referred to as pyrolitic distillation.

Gigawatt

A measure of electrical power equal to one billion watts or 1,000,000 kilowatts. A large coal or nuclear power station typically has a capacity of about 1 GW.

Grinder

A machine that reduce particles in size by repeatedly pounding them into smaller pieces through a combination of tensile, shear and compressive forces.

Group Selection

Regeneration method in which trees are removed and new age classes are established in small groups.

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Habitat

The place or environment where a plant or animal naturally or normally lives, grows and reproduces.

Heat Rate

The amount of fuel energy required by a power plant to produce one kilowatt-hour of electrical output. A measure of generating station thermal efficiency, generally expressed in Btu per net kWh. It is computed by dividing the total Btu content of fuel burned for electric generation by the resulting net kWh generation.

Heating Value

The maximum amount of energy that is available from burning a substance.

Higher Heating Value

The maximum potential energy in dry fuel. For wood, the range is from 7,600 to 9,600 Btu/lb.

Hog Fuel

Biomass generated by grinding wood and wood waste for use in a combustor.

Hydrocarbon Feedstock

Petroleum (hydrocarbon) based substance used as a raw material in an industrial process. Examples of petrochemical feedstocks are ethylene, propylene, butadiene, benzene, toluene, xylene, and naphthalene.

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Improvement Cutting

Used in mixed species stands past the sapling stage where trees of undesirable species or form are removed from the main canopy to favor the more desirable species.

Incinerator

Any device used to burn solid or liquid residues or wastes as a method of disposal. In some incinerators, provisions are made for recovering the heat produced.

Inclined Grate

A type of furnace in which fuel enters at the top part of a grate in a continuous ribbon, passes over the upper drying section where moisture is removed, and descends into the lower burning section. Ash is removed at the lower part of the grate.

Indirect Impacts

The inter-industry effects of input-output analysis; the impacts above and beyond the direct effects when applied tot eh Type I multipliers.

Indirect Liquefaction

Conversion of biomass to a liquid fuel through a synthesis gas intermediate step.

Induced Impacts

The impacts of household expenditures in input-output analysis.

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Joule

Metric unit of energy, equivalent to the work done by a force of one Newton applied over a distance of one meter. One joule= 0.239 calories.

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Kilowatt

A measure of electrical power equal to 1,000 watts. 1 kW = 3412 Btu/hr.

Kilowatt Hour

A measure of energy equivalent to the expenditure of one kilowatt for one hour. For example, 1 kWh will light a 100-watt light bulb for 10 hours.

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Liberation Cutting

Removal of poor quality or un-merchantable trees to favor the growth of desirable trees.

Lignin

Structural constituent of wood and (to a lesser extent) other plant tissues, which encrusts the cell walls and cements the cells together.

Logging residues

The unused portions of growing-stock and non-growing-stock trees cut or killed by logging and left in the woods.

Log Trailer

A trailer designed to haul trees, poles, or shortwood in racks. They are lightweight and because of this have high payload capacities. Most require unloading equipment at the receiving facility, although some are modified to drop one side of the log restraints and allow a front loader to push the load off one side of the trailer.

Low Thinning

Removal of smaller, weaker, and most deformed trees whose crowns are in the lower portion of the stand canopy.

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Marginal Cost Method

Cost accounting method that counts only the additional costs from the conventional logging operation as the biomass production cost.

Mill Residues

Excess material generated from wood processing mills and pulp and paper mills.

Moisture Content

The weight of the water contained in wood, usually expressed as a percentage of weight, either oven-dry or as received (green).

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Net Energy Yield

The net energy yield refers to the gross energy produced by the biomass, minus the energy provided from the fossil fuels used in the production and processing of the biomass. It is usually expressed on a per unit basis.

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One-pass Method

This is when biomass and roundwood or sawlogs are harvested and recovered silmultaneously.

Output

The value of production by industry for a specific time period.

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Petrochemical Feedstock

Petroleum (hydrocarbon) based substance used as a raw material in an industrial process. Examples of petrochemical feedstocks are ethylene, propylene, butadiene, benzene, toluene, xylene, and naphthalene.

Petroleum-based Feedstock

Petroleum (hydrocarbon) based substance used as a raw material in an industrial process. Examples of petrochemical feedstocks are ethylene, propylene, butadiene, benzene, toluene, xylene, and naphthalene.

Pre-commercial Thinning

Thinning that occurs when trees are too young, too small, or of species undesirable to be used for traditional timber products.

Process Heat

Heat used in an industrial process rather than for space heating or other housekeeping purposes.

Producer Gas

Fuel gas high in carbon monoxideand hydrogen, produced by burning a solid fuel with insufficient air or by passing a mixture of air and steam through a burning bed of solid fuel.

Pyrolysis

The thermal decomposition of biomass at high temperatures (greater than 400° F, or 200° C) in the absence of air. The end product of pyrolysis is a mixture of solids (char), liquids (oxygenated oils), and gases (methane, carbon monoxide, and carbon dioxide) with proportions determined by operating temperature, pressure, oxygen content, and other conditions.

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Salvage Cutting

Removal of trees that have dead, damaged, or are expected to die, generally as a result of natural disaster.

Sanitation Cut

Removal of dead and weaker trees in an overstocked stand to reduce the danger of natural disasters.

Seed-tree Silvicultural System

A silvicultural system in which all trees are harvested except for a small number of selected trees are retained for seed production for natural regeneration.

Shelterwood Silvicultural System

A silvicultural system in which trees are removed in a series of cuts, leaving those needed to produce sufficient shade to produce a new age class in a moderated microenvironment.

Short-rotation Woody Crops

Fast growing species, such as willows and poplars, which are grown specifically for the production of energy.

Shredder

A machine that tears material apart by shearing rather than smashing.

Silviculture

Science and art of managing the establishment, growth, composition, and quality of forest stands and woodlands for the desired needs and values of landowners and society on a sustainable basis.

Site Productivity

Combination of soil and climatic factors contributing to plant growth and development; may be measured as biomass accumulation as a function of time.

Skidder

Machinery used to pull logs from stump to a road-side landing. Logs are pulled with a grapple, cable-winch, or clam-bunk.

Soil Fertility

The total availability, concentration, and amount of essential plant nutrients.

Soil Function

The role that soils play in the environment and managed landscapes.

Soil Productivity

The capacity of a soil to contribute to the production of a crop, whether it is agricultural crops or forest biomass.

Streamside Management Zones

Buffer zones in which cover is retained in riparian areas adjacent to surface water and aquatic habitat.

Sustainability

The capacity of forests, ranging from stands to ecoregions, to maintain their health, productivity, diversity, and overall integrity, in the long run, in the context of human activity and use.

Sustainable Forest Management

Forest management that ensures that forest resources will be managed to supply goods and services to meet the current demands of society while conserving and renewing the availability and quality of the resource for future generations.

Sustained Yield

A forest management strategy in which the net growth and yield are such that a forest can produce continuously at a given intensity of management.

Syngas

A gas mixture that contains varying amounts of carbon monoxide and hydrogen generated by the gasification of a carbon containing fuel to a gaseous product with a heating value.

Silvicultural practice of reducing tree numbers in a stand in order to favor the growth and health of the remaining crop trees.

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Transpiration Drying

The natural drying that occurs in biomass material leafy material is left on the tree. Water evaporates from the various leaf parts, in particular the stomata.

Tree-length

Trees are felled, delimbed, and topped in the stump area and processed at the landing.

Two-pass Method

This is the harvesting and recovery of roundwood and biomass in separate passes. In this system, the unconsolidated biomass is either left in woods out of the way or is piled near the landing for later recovery by the current contractor or a subsequent contractor.

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Uneven-aged Management

Regeneration and management technique that removes some trees in all size classes either singly, in small groups, or strips in order to maintain a multi-aged stand.

Urban Residues

Wood and yard waste; construction and demolition debris.

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Value-added

Payments made by industry to workers, interest, profits, and indirect business taxes.

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Water Quality

Suitability of the water coming from ground and surface water supplies for drinking water, recreational uses, and as habitat for aquatic organisms and other wildlife.

Water Quantity

Timing and total yield of water from a watershed.

Whole Tree

Trees are felled and transported to roadside with branches and top intact. Processing occurs at the roadside landing.

Wood Ash

Ash recovered from the combustion of woody biomass; may be used as fertilizer or soil liming agent to reduce soil pH.

Wood Processing Residue

The unused portion of materials generated during wood processing or by-products created during the pulping process.

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