BLM landLand administered by the Bureau of Land Management.
blockA repetition/replication of the Early, Mid and Late Seral Treatment plots and a Control plot. See Repetition/replication.
Block Group (BG)(BG)A cluster of census blocks having the same first digit of their four-digit identifying numbers within a census tract.
Block-faulted (mountains)Landforms formed by the movement (uplift and tilting) of large crustal blocks during an extensional episode.
BlowdownPeriodic removal of water from an evaporative cooling system (also known as a wet closed-cycle cooling system) to control the buildup of impurities and…
BlowoutA wind-eroded section of a sand dune caused by a disturbance or removal of the vegetation.
Board feet (BF)(BF)Unit of measure for logs and lumber. One board foot is equivalent to a piece of wood 1 inch thick, 12 inches wide, and 12 inches long.
BOD5The amount of dissolved oxygen consumed in five days by biological processes breaking down organic matter. See biochemical oxygen demand.
BoilerA vessel or tank where heat produced from the combustion of fuels such as natural gas, fuel oil, or coal is used to generate hot water or steam for…
Boiler HorsepowerA unit of rate of water evaporation equal to the evaporation per hour of 34.5 pounds of water at a temperature of 212 degrees Fahrenheit into steam at 212…
Bolson (floor)A term applied to an internally drained (closed) intermontane basin in arid regions where drainages from adjacent mountains converge toward a central…
Bone dryHaving zero percent moisture content. Wood heated in an oven at a constant temperature of 212 degrees F or above until its weight stabilizes is considered…
Bone dry ton(or "oven dry ton"). An amount of wood that weighs 2,000 pounds at zero percent moisture content.
Bone dry unit (BDU)(BDU)A quantity of wood residue which weighs 2,400 pounds at zero percent moisture content.
BorealLiving in and adapted for living in the extreme northern areas of the world. This area is located just below tundra conditions.
BoronThe chemical element commonly used as the dopant in solar photovoltaic device or cell material.
Borrow materialMaterial such as soil or sand that is removed from one location and used as fill material in another location.
Borrow pitA pit or excavation area used for gathering earth materials (borrow) such as sand or gravel.
Bottom ashNoncombustible ash that is left after solid fuel has been burned.
Bottoming cycleA means to increase the thermal efficiency of a steam electric generating system by converting some waste heat from the condenser into electricity.
Braided streamsBraided streams have multiple channels that are interlaced in a braided pattern, with very low stream gradient (<0.
BrecciaA sedimentary rock formed of coarse-grained material consisting of sharp fragments embedded in clay or sand.
British thermal unit (Btu)(BTU)The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit; equal to 252 calories.
Broadband noiseNoise that has a continuous spectrum, that is, energy is present over a wide range of frequencies.
Broadcast burnControlled fire over the entire surface of a designated area.
BrowseTwigs, leaves, and young shoots of trees and shrubs that animals eat.
BryophytesPlants of the phylum Bryophyta, including mosses, liverworts and hornworts, characterized by the lack of true roots, stems and leaves.
BryozoanAquatic colonial animals with branching, mossy or fan-like growth. They resemble corals but have more complex nervous, muscular, and digestive systems.
Build outThe estimated extent of residential, commercial, and industrial development in a given geographic area; usually related to the upper limit of the…
Build-out capacityThe maximum total percentage of development in a watershed; typically determined assuming current zoning holds indefinitely into the future.
Bulk DensityThe weight of a material per unit of volume compared to the weight of the same volume of water.
BunchgrassA grass having a bunched growth form and lacking rhizomes.
Bureau of Land ManagementAn agency of the U.S. Department of the Interior that is responsible for managing public lands.
BurrowA hole made by an animal, usually for shelter or to move through by digging.
ButaneA gas derived from natural gas. Used as a component of gasoline. Used in liquefied petroleum gas (LPG) for domestic and industrial applications.
Butanol or butyl alcoholAn alcohol with the chemical formula CH3(CH2)3OH. It is formed during anaerobic fermentation using bacteria to convert the sugars to butanol and carbon…
Butt logThe log taken from the base of a tree; often slightly irregular.
by-productMaterial, other than the principal product, generated as a consequence of an industrial process or as a breakdown product in a living system.
C unit (CCF)(CCF)One hundred cubic feet of solid wood. Used as a log measure or as a measure of solid wood content. 1 CCF contains typically 1.4 BDT.
Cable yardingA term used to describe a means of removing logs from the stump area to a landing or yarding area through use of an overhead system of winch-driven cables…
Cadastral survey systemA survey that creates, marks, defines, retraces, or re-establishes the boundaries and subdivisions of the public land of the United States.
Cadmium (Cd)A chemical element used in making certain types of solar cells and batteries.
CairnA mound of stones erected as a memorial or marker.
CalcareousOf, containing, or like calcite (calcium carbonate).
CalderaA large, usually circular depression at the summit of a volcano, formed when magma is erupted from a shallow underground magma reservoir.
CalicheA sedimentary deposit, commonly made of calcium carbonate, and formed from the leaching of minerals from the top layers of soil.
California Ambient Air Quality Standard (CAAQS)(CAAQS)A legal limit that specifies the maximum level and time of exposure in the outdoor air for a given air pollutant and which is protective of human health…
cambium(pl.: cambia) A one or two cells thick layer of plant meristematic tissue, between the xylem and phloem tissues, which gives rise to secondary tissues…
Cancer(KAN-ser) A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the…
CapA cap is a ceiling, or the highest level to which something can go. For example, an interest rate cap limits the amount by which an interest rate can be…
CapacityYour ability to make your mortgage payments on time. This depends on your income and income stability (job history and security), your assets and savings…
Capacity factorThe ratio of the average load on (or power output of) a generating unit or system to the capacity rating of the unit or system over a specified period of…
Capital costThe total investment needed to complete a project and bring it to a commercially operable status. The cost of construction of a new plant.
carbohydrateA sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as…
Carbon Dioxide(KAR-bun dy-OK-side) A colorless, odorless gas. It is a waste product made by the body.
carbon monoxide(KAR-bun muh-NOK-side) A poisonous gas that has no color or odor. It is given off by burning fuel (as in exhaust from cars or household heaters) and…
Carbon Monoxide (CO)(CO)A colorless, odorless gas produced by incomplete combustion. Carbon monoxide is poisonous if inhaled.
Carbon SequestrationThe absorption and storage of carbon dioxide from the atmosphere. Naturally-occurring in plants.
Carbon sinkA reservoir that absorbs or takes up released carbon from another part of the carbon cycle.
Carbonate rockRocks (such as limestone or dolostone) that are composed primarily of minerals (such as calcite and dolomite) containing the carbonate ion (CO32-).
Carrying capacityThe theoretical maximum weight of fish that can be maintained in a pond without depleting the food supply.
Cascade aerationAeration of an effluent stream through the action of falling water.
catalystA substance that promotes a chemical reaction by lowering the activation energy of a chemical reaction, but which itself remains unaltered at the end of…
Catchment basinA topographic region in which all water drains to a common outlet; a watershed.
cavity(KA-vih-tee) A hollow area or hole. It may describe a body cavity (such as the space within the abdomen) or a hole in a tooth caused by decay.
CellulaseEnzyme catalysing the breakdown of cellulose.
Cellulose(SEL-yoo-lose) A building block of plant cells and fiber. Cellulose cannot be digested by people, and is used to add bulk to the diet.
CenozoicAn era of geologic time from the beginning of the Tertiary period (65 million years ago) to the present. Its name is from the Greek and it means "new life.
Census blockCensus blocks are defined by the U.S. Bureau of Census and are the smallest geographic unit for which the Census Bureau tabulates data.
Census block groupsGeographic entities consisting of groups of individual census blocks. Census blocks are grouped together so that they contain between 250 and 550 housing…
Center pivot irrigationA form of sprinkler irrigation consisting of several segments of pipe (usually galvanized steel or aluminum) that are joined together and supported by…
Central Arizona Project (CAP) Aqueduct(CAP)A 336-mi (541-km) long diversion canal operated by the Central Arizona Water Conservation District that diverts water from the Colorado River into central…
Centralized sewage treatmentThe collection and treatment of sewage from many sources to remove pollutants and pathogens.
Change-outThe routine replacement of chemicals contained in process equipment, in accordance with schedules established by the manufacturer, or as a result of…
Channel incisionThe process of downcutting into a stream channel leading to a decrease in the channel bed elevation.
ChaparralA plant community of shrubs and low trees adapted to annual drought and often extreme summer heat and also highly adapted to fires recurring every 5 to 20…
CharA byproduct of low-temperature carbonization of a solid fuel.
Chemical oxygen demand (COD)(COD)The amount of dissolved oxygen required to combine with chemicals in wastewater.
ChertA hard, dense, fine-grained type of sedimentary rock; a microcrystalline aggregate of silica (quartz).
Chip vansSpecial construction bottom dump trucks (grain trucks) or conventional tractor- trailer vans used for hauling pulp chips, mill residues, hog fuel, and…
ChipperA machine that produces wood chips by knife action.
CHIPSWoody material cut into short, thin wafers. Chips are used as a raw material for pulping and fiberboard or as biomass fuel.
ChlorofluorocarbonA family of chemicals composed primarily of carbon, hydrogen, chlorine, and fluorine. Used principally as refrigerants and industrial cleansers.
ChokerA cable loop that is attached to a log during the yarding process.
Chronic effectsEffects resulting from exposure to low levels of a stressing factor (e.g., contaminant, disease, electromagnetic field, noise, and radionuclides) over…
CienegaA perennially wet area supported by a spring or other water source; also called wetland, marsh, or swamp.
Cinder coneA conical hill formed around a volcanic vent by the accumulation of loose cinders and other pyroclastics ejected during a volcanic eruption, normally…