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The Forester’s Corner helps children investigate Colorado’s forests close up and at a distance.

Just for Kids! Foresters's Corner

CSFS Kids’ Glossary

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*Adaptation: The process of adjusting to the environment, for better survival, over time. For example, a plant with unusually long roots will be better at absorbing water over a larger area than plants with shorter roots, making long rooted plants more likely to survive during periods of drought.

Annual Rings: The rings found within the cambium layer of a tree that represent one growing season within the tree’s life. Counting the annual rings on a tree will tell you how old a tree is and help determine what the weather was like during one year of a tree’s life.

*Bark: The tough exterior covering of a tree, shrub, woody root or stem.

*Biodiversity: The variety of life on Earth, reflected in the variety of ecosystems and species, their processes and interactions, and the genetic diversity within and among species.

Branch: The large side shoots that come out of the tree’s trunk and reach into the heartwood of the tree.

Browse: The leaves, twigs and shoots on trees in forests that grazing animals feed on.

*Cambium: A thin layer of living, dividing cells just under the bark of trees. This layer gives rise to the tree’s secondary growth.

*Canopy: The forest layer formed by the leaves and branches of trees or shrubs. There may be several canopy layers in a forest.

*Carbohydrates: Sugars, starches and celluloses that are produced by green plants and are important nutritional sources of energy for many animals.

*Chlorophyll: A group of pigments that produce the green hue of plants, essential to photosynthesis.

*Chloroplasts: The structures within plants that contain chlorophyll and enable photosynthesis to occur.

Coleoptera: The beetle order. All beetles in the order Coleoptera have hardened outer wing coverings called elytra, chewing mouthparts and undergo a complete life cycle (metamorphosis).

Coniferous: A plant that bears its seeds as cones and generally produces narrow, needle-like leaves.

Cork Cells: A layer of cells within trees that provide extra protection to the tree in case the bark is cracked or damaged.

Crown: The upper part of a tree composed of the tree’s leaves, branches, twigs, flowers and fruits.

Crown Fire: A fire that advances through the tops of tree or shrub crowns

*Deciduous: A plant that periodically (typically in autumn) loses its leaves. Most American broadleaf trees are deciduous. A few conifers, such as the larch and cypress, also are deciduous.

*Defoliation: The loss of leaves from plants, usually because of insects, disease or stress.

Disturbance: An event that causes changes in the composition and structure of a forest, such as a wildland fire, drought, insect infestation, disease, flood, avalanche or windstorm.

Dormant: The inactive state that a tree will remain in during the cold winter months to withstand a lack of water.

Ecology: The scientific study of the relationships between living organisms and their environment.

Ecologist: A scientist that studies the relationships between living organisms and their environment.

*Ecosystem: The interacting system of a biological community and its nonliving environment.

Elytra: The hardened outer wing coverings on beetles in the Coleoptera order.

Epidemic: A situation in which plants, animals or disease rapidly spread and harm many individuals within a population.

Evergreen: A tree, shrub, or plant with foliage that remains green throughout the year.

Fire Ecology: The study of fire and its effects in ecosystems.

Fire Management: Actions to prevent wildland fires, stop them, or manage them for particular purposes, such as improving wildlife habitat.

Fire Suppression: The act of putting out a wildfire.

Fire Triangle: A representation of the three things required to start a fire: oxygen, heat and fuel. If any side of the triangle is missing, a fire cannot start. If any side of the triangle is removed, then the fire will go out.

FireWise: Guidelines for homeowners to follow to help keep their homes and properties safe from wildfires.

*Forest Management: The proper care and control of wooded land to maintain forest health, soil condition, water quality, wildlife habitat, production of wood products, beauty and other values, to accomplish specific objectives.

Fuel: Any living or dead material that will burn, such as dry leaves, fallen branches, pine trees, grasses or even homes.

Gallery: The tunnels that beetles burrow inside of the bark of a tree. The gallery is where the beetles will lay their eggs, and where the younger beetles will live during the winter until they grow into adults.

Ground Fire: Fire that consumes the organic material beneath the surface litter ground.

Hazardous Fuels: Dry fuels, such as grasses, downed branches, ladder fuels and trees that have gathered over time and increase the possibility of large wildland fires.

Heat: A form of energy that raises the temperature of matter.

*Heartwood: The older, harder, nonliving central portion of wood in some trees that is usually darker, denser, less permeable and more durable than the surrounding sapwood. This wood is the main support for the tree.

Hillslope Stabilization Treatments: Using groundcover, such as fallen trees, new grasses and even hay, to cover up bare soil and catch running water to prevent flooding and water runoff after a fire.

Hydrophobic: Objects that tend to repel or not absorb water. Soils can become hydrophobic after they have been burned and will not absorb water.

Interface: The boundary or the overlap between two different areas or things, such as housing developments and forests.

Ladder Fuels: Plants and other living and dead materials that provide a path between fuels on the ground to the branches and crowns of trees, sometimes resulting in high-intensity crown fires.

Larvae: The newly hatched, wingless form of an insect before it goes through the process of metamorphosis.

Lateral Buds: Places of growth on the side of twigs where branches begin to form.

Leaf/Leaves: The organs on plants that produce food for the plant through the process of photosynthesis. Leaves can be narrow or broad, bladelike or needlelike, oval, triangular or round, smooth or ragged.

Metamorphosis: The transformation of a larva into an adult, such as a caterpillar into a butterfly.

Mosaic: A collection of diverse habitats or landscapes created by wildfires.

Mycangium: The little grooves on the back of the mountain pine beetle where the bluestain fungus attaches.

Native: Living or growing naturally in a particular place.

Needles: Modified narrow, needle-like leaves on coniferous trees and shrubs.

Nutrients: A substance that an organism needs to live and grow, which is taken from the organism’s environment.

Over-browsing: When animals eat too much of the twigs, leaves and shoots on trees and reduce a tree’s ability to grow.

Parasitic: Describes a relationship in which an organism (the parasite) lives in or on another (the host) from which it obtains nourishment. This may weaken or even kill the host.

Pheromones: A chemical that influences the behavior of other individuals of the same species. In a mountain pine beetle outbreak, beetles release the chemical smell that tells other beetles “this tree is full, go somewhere else.”

Phloem: A layer of tree tissue that is just inside the bark. The phloem transports food and nutrients for the tree from the leaves to the stem and roots.

*Photosynthesis: The process by which green plants manufacture simple sugars in the presence of sunlight, carbon dioxide and water. Chlorophyll is essential to the series of complex chemical reactions involved.

*Prescribed Burn: The planned application of fire to a forest, stand, prairie or slash pile with the intent to confine the burning to a predetermined area.

Pupa: The stage in the metamorphosis of an insect between the larva and the adult when the organism is not feeding, sometimes known as a cocoon.

Ray Cells: The dark streaks that reach from the outside of the tree to the tree’s interior and transport waste throughout the tree.

Resin: A sticky substance that pine trees release when wounded. This happens when beetles try to burrow into the bark of a tree and resin is released in an effort to expel the beetles from the tree.

Roots: The underground extensions of a tree that collect nutrients and water and anchor the tree to the ground.

Sapwood: The layer of the tree between the heartwood and the cambium that carries water, minerals and plant sugars throughout a tree using xylem and phloem tissues.

Serotinous Cones: Cones that require a source of heat to open and release their seeds.

Shrubland: An area occupied by woody plants, which are less than 12 feet tall and usually have more than one stem rising from the ground.

Springwood: The light colored cells produced by the growing cambium layer of the tree in the spring.

Suckers (also known as sprouts): The name for new aspen trees that are produced from underground by older aspen tree roots because of increased soil temperatures.

Summerwood: The darker colored cells produced by the growing cambium layer of the tree in the summer.

Surface Fire: Fire that burns loose debris on the surface including dead branches, leaves and low vegetation.

Symbiotic: A relationship between two or more different organisms of different species where both of the participants in the relationship may benefit in some way.

Terminal Buds: The extensions at the end of twigs that cause the twigs to grow longer.

Terminal Bud Scale Scars: Scar-like abrasions on twigs that show where the terminal buds on a tree were located before they fell off for the year.

Trunk: The single main stem of a tree that provides the tree with structure.

Twig: The part of a tree’s trunk that attaches the leaves to the tree.

Urban: Describing a city or a town where people live and work and go to school.

Wildfire: Uncontrolled fires that burn in the country or in wilderness or wildland areas.

Wildland: An area where there is essentially no human development or man-made structures.

Wildland-Urban Interface: The boundary or overlap between wildlands and urban areas. In other words, the wildland-urban interface is the place where man-made structures (like the ones found in urban areas) are close to or within natural landscapes (or wildlands) where surrounding vegetation can catch fire easily. There is a high chance of wildfires starting in the wildland-urban interface.

*Woodland (or open forest): A wooded area in which the crowns of the trees do not form a closed canopy. (In other words, the leaves and branches of the trees and shrubs do not touch.)

Xylem: The tissues within the tree bark that transport water from the roots to the crown of the tree.

*Project Learning Tree definitions:
American Forest Foundation. Project Learning Tree: Pre K-8 Environmental Education Activity Guide. 2008.

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