Forestry Terms  - C -

CALIPER -Instrument for determining tree and log diameters by measuring their rectangular projection on a straight graduated
rule via two arms at right angles to (and one of them sliding along) the rule itself.
-The optical caliper determines upper, out-of-reach tree diameters through an optical system incorporating two parallel lines of
sight separated by a variable baseline.

CALKS (caulks) -Short, hobnail-like spikes in the soles and heels of boots, designed to give secure footing while walking on
logs. Also known as corks.

CAMBIUM -Layer of living cells between the wood and the innermost bark of a tree. Each growing season the cambium adds anew layer of cells (by cell division) on the wood already formed, as well as a layer of inner bark on the cambium's outer face.

CANOPY - A layer or multiple layers of branches and foliage at the top or crown of a forest's trees.

CANOPY COVER: The percent of a fixed area covered by the crown of an individual plant species or delimited by the vertical projection of its outermost perimeter; small openings in the crown are included. Used to express the relative importance of individual species within a vegetation community or to express the canopy cover of woody species. Canopy cover may be used as a measure of LAND COVER change or trend and is often used for wildlife habitat evaluations.

See also CROWN CLOSURE.

CAPITAL GAINS - Profit on the sale of an asset such as timber, land, or other property. Reporting timber sales as capital gains provides certain tax advantages over reporting revenues as ordinary income.

CASCADES: The steepest of riffle habitats. Unlike rapids, which have an even gradient, cascades consist of a series of small steps of alternating small waterfalls and shallow pools. The usual substrate of cascades is bedrock or an accumulation of boulders; however, this habitat type is occasionally found on the downstream face of woody debris dams.

CATION EXCHANGE CAPACITY: The sum of exchangeable cations that a soil, soil constituent, or other material can adsorb at a specific pH. Cation exchange capacity is a laboratory analyzed value

CAUSE OF DEATH/INJURY: The nominal most obvious cause of death for mortality trees or the most important cause of injury to live trees. To be judged as important, the injury must be serious enough now or in the future to (1) ultimately cause death, (2) predispose the tree to fatal attack by another agent, or (3) significantly reduce diameter or height growth.

CHANNEL DEPTH: The average depth of a stream channel from mean high water mark to mean high water mark. Categorization of the entrenchment and confinement is accomplished by visual analysis or by aerial photos.

CHANNEL GRADIENT: The slope of the stream channel expressed on a percent of rise per unit length. A measure of the drop in water surface elevation per unit length of channel. Channel gradient is a parameter used in model building, channel hydraulics and flow response water yield, water use, instream and flood hazard.

CHANNEL ROUGHNESS: A roughness coefficient to determine stream flow velocity and used to determine energy losses and velocities of natural stream channels.

CHANNEL STABILITY RATING: A rating of a stream channels resistance capacity to the detachment of bed and bank materials.

CHANNEL SUBSTRATE: The composition of the channel substrate (stream channel bed materials).

CHEMISTRY, ATMOSPHERIC: The chemical composition of ambient air used to understand the degree of air pollution impact occurring on public lands and to determine the type of resource management recommendations to be made to regulators.

CHEMISTRY, pH DRY DEPOSITION: The pH of particles and aerosols deposited at the surface. Used to judge the impact of air pollutants on living and non-living public land resources.

CHEMISTRY, pH WET DEPOSITION: The pH of precipitation used to judge the impact of acid precipitation on living and non-living public land resources.

CHEMISTRY, SNOWPACK: Chemical composition of undisturbed accumulated snow.

CHEMISTRY, WATER: This variable includes all the chemical constituents of water, including BOD, DO, nutrients, trace metals, and other organics and inorganics. Used to measure and evaluate suitability of water for various beneficial uses.

CHIP -Small piece of wood used to make pulp. Chips are made either from wood waste in a sawmill or pulpwood operation,
or from pulpwood specifically cut for this purpose. Chips are larger and coarser than sawdust (12).

CHIP-n-SAW - A cutting method used in cutting lumber from trees that measure between 6 and 14 inches diameter at breast height. The process chips off the rounded outer layer of a log before sawing the remaining cant or rectangular inside section into lumber. Chip-n-saw mills provide a market for trees larger than pulpwood and smaller than sawtimber.

CHIP UNIT -Chip volume equal to 1 cord of pulpwood.

CHOKED -Condition in which a log is attached to a skidding unit by means of a wire rope or chain choker.

CHOKER -Short length of flexible wire, rope, or chain used to attach logs to a winch line or directly to a tractor.
-Noose of wire rope for hauling a log . -Short length of wire rope that forms a noose around the end of a log to be skidded and is attached to the skidding vehicle or to the butt rigging in a wire rope logging system .

CHOKERSETTER -Person in a logging operation who places the choker around the log to be hauled to the landing.
-Beginning job for novice loggers .  --One who attaches chokers to logs in the woods for the skidding unit .

CLEAR-CUT HARVEST - A harvesting and regeneration method that removes all trees within a given area. Clear-cutting is most commonly used in pine and hardwood forests, which require full sunlight to regenerate and grow efficiently.

CLIMATE TYPE: The classified prevailing weather condition of a region.

CLIMAX COMMUNITY - A relatively stable and undisturbed plant community that has evolved through stages and adapted to its environment.

CLIMAX FOREST -Plant community dominated by trees representing the culminating stage of natural succession for that specific locality and environment.

CLIMAX SPECIES -Plant species that will remain essentially unchanged in terms of species composition for as long as the site
remains undisturbed.

CLINOMETER -Hand instrument used by foresters and timber cruisers to measure vertical angles. Such angles, when correlated with specific distances, indicate the height of standing trees .

CODOMINANT TREES: Trees or shrubs with crowns receiving full light from above, but comparatively little from the sides. Crowns usually form the general level of the canopy. (In stagnated stands will be small-sized and crowded on the sides).

COMMERCIAL THINNING -Partial harvesting of a stand of trees for economic gains from the harvested trees and to accelerate the growth of the trees left standing.

COMPETITION - The struggle between trees to obtain sunlight, nutrients, water, and growing space. Every part of the tree - from the roots to the crown - competes for space and food.

CONCENTRATION YARD -Pulpwood yard providing facilities for unloading trucks, storage, and loading for shipment.

CONIFER -Tree that is a gymnosperm, usually evergreen, with cones and needle-shaped or scalelike leaves, producing wood
known commercially as softwood .

CONK -Visible fruiting body of a wood-destroying fungus, usually indicating rot in the underlying wood.

CONSERVATION -Protection, improvement, and wise use of natural resources according to principles that will assure utilization of  the resource to obtain the highest economic and/or social benefits.

CONTINUOUS FOREST INVENTORY (CFI) -Timber sampling system that provides for periodic remeasurement of specific stands or plots of individual trees; this shows status and periodic change over time for the forest as a whole and major subdivisions therein .

CONSERVATION RESERVE PROGRAM (CRP) - A federal program designed to remove highly erodible, marginal farmland from production through a one-time cost-sharing payment to establish trees, grass, or other cover. The landowner receives a 10-year annual rental payment to maintain the cover.

CONTOUR FELLING -Timber felled parallel to ground contour line.

CONTRACT HAULER -Independent truck owner or a driver working for the contractor who hauls logs from the woods to the dump.

CONTRACT LOGGING -Operator doing all or part of the logging for a company -Independent logger who logs standing timber according to the terms of a contract.


CONTROLLED BURNING -Use of fire to destroy logging debris, reduce buildups of dead and fallen timber that pose wildfire
hazards, control tree diseases, and clear land. Other functions of a controlled burn include clearing a buffer strip in the path of a
wildfire; see backfire (17).

CORD - A stack of round or split wood consisting of 128 cubic feet of wood, bark, and air space. A standard cord measures 4 feet by 4 feet by 8 feet. A face cord or short cord is 4 feet by 8 feet by any length of wood under 4 feet.

COST-SHARE ASSISTANCE - An assistance program offered by various state and federal agencies that pays a fixed rate or percentage of the total cost necessary to implement some forestry or agricultural practice.

COVER - (a) Any plant that intercepts rain drops before they reach the soil or that holds soil in place. (b) A hiding place or vegetative shelter for wildlife from predators or inclement weather.

CROP TREE - Any tree selected to grow to final harvest or to a selected size. Crop trees are selected for quality, species, size, timber potential, or wildlife value.

COUNTY, PARISH, BOROUGH, OR POLITICAL TOWNSHIP: The largest territorial division for local government within a state.

CROWN -Upper part of a tree, including the branches and foliage.

CROWN CLASS: The relative position of the tree or shrub crown with respect to competing vegetation surrounding the tree or shrub. Crown class for each tree or shrub is judged in the context of its immediate environment; that is, those trees or shrubs which are competing for sunlight with the subject tree. Crown class is essentially a classification of competition for light and is aimed at separating trees that are growing freely from those that are not. It designates trees or shrubs with crowns of similar development and occupying similar positions in the crown canopy. This is an ocular classification of trees or shrubs based on dominance in relation to adjacent trees or brush as indicated by crown development and amount of sunlight received from above and on the sides. In uneven-aged stands of tolerant species (in which the trees are not in small even-aged groups), trees in the intermediate crown position in the stand and with medium-sized crowns will be considered comparable to codominants of even-aged stands and coded as such. An example of this would be white spruce in an aspen or birch stand. As a general rule, in multi-story stands crown class for each tree must be judged in the context of its immediate environment, that is, those trees affecting it or being affected by it in terms of crown competition. In cases where the overstory consists of scattered veterans standing above larger numbers of younger trees, a considerable portion of the understory trees will undoubtedly be classified as dominant or codominant.

CROWN CLOSURE (COVER): The percentage of the ground covered by a vertical projection of the outermost perimeter of the natural spread of the foliage of plants. See also CANOPY COVER. Used to map and stratify stands of vegetation and as a measure of protection of a site or stream.

CROWN FOLIAGE DENSITY: A visual index of the amount of foliage per unit of crown. Used for calculation of foliage structure and a measure of the severity of defoliation and disease.

CROWN FORM (Shape): The configuration crown of a standing tree or shrub - circle, triangle, neolloid, parabola, rectangle or horizontal ellipse. Used to model vegetation structure and to determine foliage volume and percent growth cover by height.

CROWN LENGTH (Depth). The vertical distance from the top of the leader to the base of the crown, measured to the lowest live branch-whorl with live branches in at least 3 quadrants, and continuous with the main crown. Used to develop horizontal-vertical profiles and biomass estimates.

CROWN RATIO: The percent of the compacted portion of the tree bole or shrub supporting green, live, healthy foliage when compared to the total length or height.

CROWN THINNING -Removing superfluous live growth in a tree crown to admit light, reduce weight, and lessen wind resistance

CROWN VOLUME PERCENT: The percentage of a given space occupied by live foliage.

CROWN WIDTH (Diameter): The span of the crown of a tree or shrub.

CRUISE - A survey of forestland to locate timber and estimate its quantity by species, products, size, quality, or other characteristics.

CRUISER -One who conducts surveys of timber land. Also known as an estimator.

CUBIC SCALE -Estimate of the cubic-foot volume of wood fiber in a tree, log, or other wood product.

CULL -tree or log that is unmerchantable because of defects. -Logs that are rejected or parts of logs deducted in
measurement because of defect.

CULTIVATED CROPLAND: Areas that are tilled and dominated by vegetation grown for the production of food and/or fiber, provided these areas do not qualify as Treeland, Grassland, or Shrubland. Cultivated cropland includes fallow land, land in any stage of annual crop production, and land being regularly cultivated for production of crops from perennial plants. Examples are orchards; nurseries of all types; and areas dominated by such species as wheat, barley, corn, soybeans, grapes, and berries.

CUNIT -Unit of volume consisting of 100 cubic feet.-Unit of measure or stacked pulpwood that equals 100 cubic feet of solid wood (does not include bark or air volume).

CUTTING CONTRACT - A written, legally binding document used in the sale of standing timber. The contract specifies the provisions covering the expectations and desires of both buyer and seller.

CUTTING CYCLE - The planned time interval between major harvesting operations within the same stand - usually within uneven-aged stands. For example, on a 10-year cutting cycle in a hardwood stand, trees are harvested every 10 years.

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