Module 7: Woodlot Ecology: Your Living Woodlot

Glossary of Key Terms - Module 7

Acid rain: A pollutant produced when too much sulfur dioxide and nitrogen oxide are released into the air from electrical plants, smelters, other industries, and vehicles. The chemicals fall with rain and affect soil and water health.

Amino acids: The building blocks of proteins, essential for all life.

Amphibians: Animals that lay their eggs in water or moist places and have soft skin. Salamanders and frogs are examples of amphibians in Nova Scotia.

Anaerobic: In the presence of little or no oxygen.

Basal area: The area in square metres of the cross section at breast height of trees on a hectare.

Best management practices: Forestry operation procedures that strive for operator efficiency and consider potential negative impacts on the environment.

Bog: An area of land where water drainage is blocked; they all have cushiony vegetation (mosses), and an accumulation of peat.

Browse: To eat the twigs and leaves of woody plants. Deer, moose, and hares are browsers.

Cambium: The layer of tissue between the bark and wood from which new wood and bark develops.

Canopy: The top of a forest formed by the leaves and branches of the trees. The density of the canopy determines how much light reaches the forest floor.

Carbon Cycle: One of the essential nutrient cycles. Carbon dioxide is taken from the atmosphere to make food energy and then stored in trees or decayed plant and animal tissue.

Carnivores: Animals that eat animals, e.g., trout eat insects, bobcats eat hares.

Cavity trees: Living or dead trees with natural or excavated holes or cavities.

Climate: Light, temperature, wind, lightning, carbon dioxide, and precipitation combined.

Commercial thinning: A thinning in which harvested trees are removed from the site and used for commercial purposes.

Communities: Groups of plants and animals that live together. Soil and climate largely influence how communities are made up.

Coniferous: Trees with cones and needles; softwoods.

Crop tree pruning: Removing the lower branches of a crop tree to increase future wood value.

Crop tree release: Providing space, by cutting competing trees, on at least two sides of a tree for increased growth and future wood value.

Deciduous: Trees with leaves which fall off in the autumn; hardwoods.

Decomposers: Fungi and animals which break down once living material, producing essential nutrients for new forest.

Dendrochronology: The study of tree history through tree rings.

Diversity: An index of the variety of plants and animals in an ecosystem.

Ecology: The study of living things and their relationship to their environment, home, or community.

Ecosite: A particular area with similar conditions or characteristics of vegetation, soil, and climate.

Ecosystem: An interrelated and interdependent community of plants and animals and their habitats.

Edge: A zone created where two stands, two habitat types, or two successional stages meet.

Energy flow: How energy moves through an ecosystem. In the forest sun is the main energy source. This energy is converted to green plants which in turn are eaten by animals and decompose to be recycled into nutrients and used again.

Evapotranspiration: The combined loss of water from an area by evaporation from the soil surface and by transpiration from plants.

Field capacity: The percentage of water remaining in a soil after having been saturated and after free drainage has ceased.

Food chain: "Who eats who" in the ecosystem.

Food web: The groups of food chains that bind an ecosystem together.

Global warming: Heating of the Earth's atmosphere due to carbon dioxide and other gases being released and trapped in the Earth's atmosphere.

Greenhouse gases: Gases trapped in the atmosphere that are likely to cause global warming, such as carbon dioxide and methane.

Habitat: The place where an animal lives.

Habitat requirements: Food, water, shelter (cover), and space in the right combinations at the proper time of year.

Herbivores: Animals that eat plants, e.g., white-tailed deer eat red maple.

Highgrading: A way to describe harvesting systems which remove only the biggest and best trees.

Horizon: See soil horizon.

Humus: A layer of soil (usually the second layer) made up of decomposed forest litter.

Hydric soils: Soils that are saturated with water long enough to affect the growth of plants.

Intolerant: Plants and trees which do not grow well under the shade of another tree.

Layering: A type of vegetative reproduction in which a lower branch of a tree, usually black spruce, forms its own rooting system and develops into a tree.

Legacy forest: A representative remnant of an original forest that is similar in species content and tree height and age as the original forest.

Loam: A soil type that is made up of near equal amounts of clay, sand, and silt.

Marshes: Wetlands which are dominated by grasses and reeds.

Microclimate: A different climate within the same area due to slight changes in elevation, soil, etc.

Mutualism: An interaction between individuals of different species in which the growth of both are benefited.

Mycelium: Groups of fungal strands.

Mycorrhizae: A relationship between plants and fungi that aids plants in the uptake of water and nutrients.

Niche: The role an animal plays in an ecosystem.

Nitrogen Cycle: The movement of one of the necessary nutrients in the forest ecosystem. Nitrogen mainly comes from the atmosphere and is "fixed" into a usable form by plants, fungi, and bacteria.

Nutrients: The minerals in the soil and gases in the air which make plant growth possible.

Nutrient cycling: The way nutrients are moved around and used in an ecosystem.

Ozone layer depletion: An environmental problem caused by the release of chemicals called chlorofluorocarbons (CFC's) into the atmosphere which in turn causes the ozone layer to be broken down. The ozone layer protects us from ultra-violet rays of the sun.

Peat: Mosses and other plants that have decomposed in water.

Percolation: The downward movement of water through soil.

Phloem: A portion of the inner bark of a tree that transports sugars.

Photosynthesis: The process by which the sun's energy is used by plants to create sugar, oxygen, and water.

Pre-commercial thinning: A forestry treatment that thins dense stands of trees before they become of merchantable size.

Proteins: A group of nitrogen-containing organic compounds, composed of amino acids. They are essential parts of living things and one of the essential food substances of animals.

Radiation: Reflection of warmth - the sun radiates heat and trees radiate heat back into the air.

Regeneration: Seedlings or saplings that develop on a forest site.

Reptiles: Animals with protective shields or scales that lay leathery eggs on land. Snakes and turtles belong to the reptile family.

Respiration: The release of gases (mainly oxygen) when plants and animals breathe.

Selection harvesting: Maintaining an uneven-aged condition in a forest stand or woodlot by harvesting trees of various ages and sizes, in order to promote regeneration in openings and growth on the remaining crop trees.

Shelterwood: The removal of mature trees from a forest stand in several stages in order to establish natural regeneration in the partial shelter of the parent trees.

Silviculture: The science and art of growing and producing forest crops based on knowledge of tree form and life.

Snags: Standing dead trees.

Soil horizons: Distinguishable layers of soil in the ground.

Soil profile: A list of the different soil layers or horizons.

Solar energy: Energy from the sun.

Solar radiation: See radiation.

Special Management Zone: The zone on both sides of a watercourse that protects the watercourse from erosion, runoff and direct sunlight. Also called a riparian zone, buffer zone or greenbelt. This zone is protected by provincial regulations.

Sprouting: The growth of buds from the base of the stump of some hardwood tree species.

Stomata: Openings in plant leaves through which respiration and transpiration occur.

Succession: The natural replacement of one plant community by another over time.

Suckering: Growth of buds from the shallow roots of some hardwood species.

Symbiosis: A relationship between two different species of organisms in which both are benefited.

Terrestrial: Growing or living on land.

Texture triangle: A graph which assists the user in determining the texture class of a soil sample by identifying the percentage of sand, silt or clay in the sample.

Tolerant: Plants and trees which can grow under the shade of other trees.

Transpiration: The release of moisture through the skin of animals or the leaves of plants.

Trophic level: A position in the food chain, determined by the number of energy transfer steps required to reach that level.

Vegetative reproduction: The new growth of trees and plants by suckering and sprouting rather than pollination (sexual reproduction).

Water Cycle: The way water is moved through the ecosystem.

Weathering: The effect of climate on an item. Rocks "weather" to turn into soil.

Wildlife: Wild animals including, fish, amphibians, reptiles, mammals, and birds.

Xylem: Woody cells manufactured in the growing cambium of living trees.

Zooplankton: Floating or swimming aquatic animals that are an important component of the food web.