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Forest Terms



Artifact - an object with historic value that has survived from the past. (4)

Atmosphere - the gaseous envelope surrounding the Earth. (9)

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Bark - The tough outside covering of a woody stem or root (2)

Biodegradable - Being able to be broken down or decomposed by natural means (3/6)

Biomass - the term biomass has two definitions: 1) the total mass of living matter within a given unit of environmental area; or 2) plant material, vegetation, or agricultural waste used as a fuel or energy source.(9)

Buffer - a wide strip of vegetation along a body of water, retained for the purpose of protecting water quality and aquatic habitat. (8)

By-product - Something that is made in the process of making something else. (5)

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Cambium - Clusters of tree cells that produce new layers of bark and wood each year forming the tree rings that we can count to tell the age of a tree. (5)

Cambium - thin layer of living cells that produce a new layer of wood each year, forming tree rings, which we can count to tell the age of a tree. The cambium lies between the xylem and phloem layers. (2)

Carbon Cycle - movement of carbon, in its many forms (solid, liquid, and gas), between the biosphere, atmosphere, hydrosphere, and geosphere. (9)

Carbon Dioxide - A colorless, odorless gas that is formed during respiration, combustion, and organic decomposition . (2)

Carbon Sequestration - the removal and capture of available atmospheric carbon in plants, soils, oceans, or atmosphere. Trees in the forests, as well as forest products, are primary carbon sequestration mechanisms. Approximately 50% of wood consists of carbon. The place where the carbon is sequestered is often referred to as a carbon sink. (9)

Carnivore - animal that eats other animals (i.e. hawk, bobcat, shark). (1)

Cells - the basic building blocks of living things. (3)

Cellular Respiration - the chemical breakdown of glucose to produce energy. This process is the opposite of photosynthesis. (2)

Cellulose - The material that makes up plant cell walls. (3)

Chlorophyll - the green substance found in leaves and needles that captures the sun's energy. (2)

Compost - A collection of organic scraps and garbage that decomposes and becomes good fertilizer. (6)

Condensation - the process of water vapor in the atmosphere turning into liquid water forming clouds. (8)

Conifer - a cone-bearing evergreen tree. (5)

Consumer - organisms that cannot make their own food, and must consume other organisms to get energy. (1)

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Decompose - To decay or come apart. (6)

Decomposer - organism that absorbs nutrients from non-living material such as dead plants and animals and wastes of living organisms then recycles these nutrients so they can be used again by plants (i.e. bacteria, fungi). (1)

Decomposition - the breakdown of organic material into smaller molecules which are then recirculated or used again by another organism. This is nature’s way of recycling. During the process, carbon dioxide is released into the atmosphere. (9)

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Ecology - the study of how plants and animals interact with each other and their environment. (1)

Emission - the act of releasing or putting a substance into circulation making it available for chemical reaction. Often the word emission is a term used to describe pollution such as the gases given off by an automobile or a large forest fire; however it can also be used to describe gases that are given off by a tree or a human and released into the air. Contrast with Sequestration. (9)

Erosion - the natural process by which Earth’s surface is worn away by the forces of wind and water—water running downhill is the primary agent in shaping topography. (8)

Erosion - the wearing away of the soil, usually by wind or water. (4)

Evaporation - the process of liquid water turning into water vapor from water and land surfaces. (8)

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Fiber - thin threads that bind together to form animal and plant matter. (3)

Food Chain - pathway along which food is transferred from one feeding level of organisms to another. (1)

Food Web - the interconnected food chains of an ecosystem. (1)

Fossil Fuels - fuels such as oil, natural gas, and coal. These combustible materials are found in the Earth’s crust and are the remains of prehistoric organisms. Burning fossil fuels typically results in a release of high levels of carbon into the atmosphere. Fossil fuels are a non-renewable resource. (9)

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Global Warming - the theory that Earth’s surface temperature is rising as a result of the increased concentrations of various gases in the atmosphere called greenhouse gases. (9)

Greenhouse Effect - the effect of various gases within the Earth’s atmosphere reflecting radiant energy back to the Earth’s surface similar to the effect which occurs in a greenhouse. Greenhouse gases, such as CO2 (carbon dioxide), methane, and ozone, insulate and warm the Earth’s surface. Without the Greenhouse Effect, life on Earth, as we know it, would not be possible and there would be no liquid water on the Earth. The greenhouse effect may be enhanced by increased levels of greenhouse gases in the atmosphere thus causing a greater warming of the Earth’s surface temperatures (Global Warming). (9)

Groundwater - water that is stored beneath the surface of the land, in spaces between rocks and soil particles—this water oft en supplies wells or springs. (8)

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Habitat - the place that is home to a plant or animal. (5)

Heartwood - the hard, inactive wood at the center of the tree. (2)

Herbivore - animal that eats plants (i.e. deer, rabbit). (1)

Hydroelectric Plant - a place where electricity is produced by the energy of rapidly moving water. (4)

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Infiltration - the process by which water from the ground surface enters the soil. (8)

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Landfills - Places in our communities where garbage is unloaded and then covered over with dirt and packed down. (6)

Lignin - The sticky substance that binds plant cells together (3)

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Natural Regeneration - the process by which seeds sprout to produce seedlings in the wild, without the use of a nursery to cultivate them. (5)

Natural Resource - material we use from our environment for housing, clothing, food energy, etc. Natural resources can be classified as renewable or non-renewable. (3)

Natural Resources - things we use that come from the earth (6)

Non-Renewable Resource - exists in a limited amount that takes thousands of years to replenish. Examples are fossil fuels like coal, oil and natural gas. (3)

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Omnivore - animal that eats both plants and other animals (i.e. bear). (1)

Organic - material made of carbon; made of living matter. (6)

Oxygen - an element found freely in nature that is needed for humans and animals to be able to breathe and is necessary for nearly all combustion to occur. (2)

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Phloem - layer of inner bark cells that transport food made by photosynthesis in the leaves to the rest of the plant. (2)

Photosynthesis - the process of channeling energy from the sun by means of chlorophyll and converting the carbon dioxide in the air to produce nutrients for the tree and oxygen that is released into the atmosphere. (2)

Photosynthesis - the process whereby plants make the carbohydrates glucose, sucrose, and starch from sunlight, carbon dioxide, and water. During this process oxygen and water are released as byproducts. The carbon from the carbon dioxide is made into carbohydrates which are either used or stored. The carbohydrates that are used are converted to energy through the process of respiration; carbon dioxide and water are formed as byproducts. See Respiration. The carbon that is stored in the plant is said to be sequestered. See Carbon Sequestration. (9)

Precipitation - occurs when so much water has condensed that the air can’t hold it anymore and it falls back to Earth as rain, snow, sleet, hail, frost, dew, etc. (8)

Prescribed Burn - to deliberately burn forest fuels under specific environmental conditions that allow the intensity and rate of fire spread to be controlled to achieve specific management objectives. (5)

Producer - organisms that use energy from sunlight to make their own food through photosynthesis (i.e. trees). (1)

Pulp - the mash (3)

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Recyclable - being able to be utilized again, often by being restructured into something else. (3/6)

Renewable - having the capability of replenishing itself. (6)

Renewable Resource - has the capability of replenishing itself in a human lifetime. For example, if a tree is harvested, it will regenerate from a seed that was dropped from a cone or planted by a human. (3)

Respiration - the process whereby plants and animals convert carbohydrates, water, and oxygen into energy, carbon dioxide and water are released as byproducts of this process. Both photosynthesis and respiration occur in plants. The difference between the carbon uptake through photosynthesis and carbon release through respiration is called net carbon uptake and is the amount of carbon that is sequestered. See Photosynthesis. (9)

Riparian Area - the area next to a river or stream inhabited by plants and animals that requires constant moisture. (8)

Riparian Zone - the area along a river or a stream. (4)

Roots - the network below ground that anchors the tree in the soil. Root hairs push their way through the soil and absorb moisture and minerals from the soil. (2)

Runoff - water that does not infiltrate the soil, but runs off the surface of the land. (8)

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Sapwood - newly formed wood cells that lie just inside the cambium. It acts as a major conductor of water and minerals for the tree; also known as xylem. (2)

Sequestration - the act of forming a stable compound so it is not available for chemical reaction. Contrast with Emission. See also Carbon Sequestration . (9)

Sink and Source - within the carbon cycle, a sink is any location where carbon is stored. A source is any location in the carbon cycle where carbon is released or made available for chemical reaction. Some examples of carbon sinks are forests, soil, and the ocean. A sink may be temporary. Carbon sinks can turn into carbon sources; for example, fossil fuels are sinks while they are buried in the Earth and wood is a sink. When the fossil fuels or wood are burned, carbon is released into the atmosphere and it is now called a carbon source. (9)

Spawning - the producing or depositing of eggs by fish. (4)

Spring - the point where groundwater flows out of the ground. (8)

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Topographic Map - a map showing changes in elevation, land features, etc. (8)

Transpiration - the process of water that has been taken up by plants, evaporating from the leaves of plants. (8)

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Watershed - an area of land where water and sediments drain into a common stream, lake or bay. (8)

Web of Life - the network of relationships that interconnects all members of an ecological community. (1)

Wildfire - a fire that is burning out of control and unpredictably. (5)

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