Glossary

Acre – An area of land that contains 43,560 square feet.

Adaptation – The process of figuring out how to meet existing management goals despite changing conditions, often referred to when discussing woodland management objectives under climate change.

Advance regeneration (reproduction) – Seedling-size trees present in a stand before a harvest aimed at regenerating the stand.

Age class – A year or defined period of years within the life of a tree stand.

Agroforestry – The practice of integrating the management of trees, crops, and livestock on the same piece of land.

All-aged stand – A stand that contains trees of all, or almost all, age classes. Also called “uneven-aged” stand. Contrast with an “even-aged” stand.

Alley cropping – An agroforestry practice where agricultural or horticultural crops are grown in the alleyways between widely spaced rows of woody plants.

Alluvial soil – Soil deposited when flowing water slows down and suspended sediment drops to the bottom.

Artificial regeneration (reproduction) – See regeneration.

Aspect – The compass direction toward which a slope faces.

Basal area – 1) Of a tree: the cross-sectional area (in square feet) of the trunk at breast height (4.5 feet above the ground). For example, the basal area of a tree 14 inches DBH is approximately 1 square foot. 2) Of an acre: the sum of basal areas of the individual trees on the acre. A well-stocked northern hardwood stand might contain 80 to 100 square feet of basal area per acre.

Block – An area of woodland based on geographic boundaries, tree species composition, timber products, accessibility, or other stand characteristics.

Board foot – A unit for measuring wood volumes equaling 144 cubic inches. It commonly is used to measure and express the amount of wood in a tree, sawlog, veneer log, or individual piece of lumber. For example, a piece of wood 12 inches x 12 inches x 1 inch and one measuring 12 inches x 3 inches x 4 inches each contains 1 board foot of wood.

Bole – The main trunk or stem of a tree.

Bolt – A short log or a squared timber cut from a log, commonly 8 feet long.

Broadcast burn – A controlled fire that is set purposely to burn across an area and eliminate woody debris and undesirable small trees and shrubs.

Browse – Growing leaves, shoots, or twigs used as animal fodder. As a verb, to feed on leaves, shoots, or twigs.

Buck – The process of cutting a tree stem into logs.

Burl – An abnormal growth of woody tissue protruding outward from a tree stem. Usually rounded in shape.

Canopy – The highest horizontal layer of vegetation in a forest made up of tree crowns.

Certification – Forest certification is a voluntary process by an authorized forester that verifies whether your forest management, including harvesting timber or other products, is environmentally appropriate, socially beneficial, and economically viable.

Chain – A distance of 66 feet.

Cleaning – See release cutting.

Clearcut – A harvesting method that removes all the trees on an area in one operation. Regeneration occurs from seed or seedlings present before cutting, from dormant seed on the ground, from seed that disperses from adjoining stands, or from artificial planting or seeding. Clearcutting is used most often with species that require full sunlight to reproduce and grow well. Produces an even-aged forest stand.

Clone – A group of plants derived from a single individual through asexual (vegetative) reproduction.

Codominant – See crown classification.

Commercial cut – A timber harvest for which the value of cut timber exceeds the cost of cutting.

Conifer – A tree belonging to the order Coniferales that usually is evergreen, cone-bearing, and has leaves that are needle-, awl- or scale-like, such as pine, spruce, fir, and cedar; often referred to as softwood.

Conservation – The protection, improvement, and wise use of natural resources to assure the attainment of their highest economic and social values over a long time period.

Cord – A stack of logs containing 128 cubic feet of wood, bark and air space. Normal dimensions of a standard cord are 4 feet x 4 feet x 8 feet. In the Lake States, pulpwood cords usually are 4 feet x 4 feet x 100 inches.

Crop tree – A tree that will be grown to economic or physical maturity. Usually selected on the basis of its species, location with respect to other trees, and quality.

Crown – The leaves and branches of a tree.

Crown classification – Ranking of individual trees in a stand according to the size and height of their crowns. In descending order of crown height and size, the classes commonly used are dominant, codominant, intermediate, and suppressed.

Crown ratio – Percentage of total tree height that is occupied by living branches.

Cruise – Process of collecting stand inventory information such as tree volumes.

Cubic foot – A wood volume measurement containing 1,728 cubic inches, such as a piece of wood measuring 12 inches on a side. A cubic foot of wood contains approximately 6 to 10 usable board feet of wood.

Cull – A tree or log of merchantable size but no market value because of serious wood quality defects.

Cutting – A segment of a tree stem, usually about 12 inches long, that can be planted to grow a new tree. The practice of severing a tree stem to fell it.

Cutting cycle – The planned time interval between major harvesting operations in a stand. The term usually is applied to uneven-aged stands. For example, a cutting cycle of 10 years means that a harvest would be carried out once every 10 years in a stand.

DBH – The diameter of a tree stem at breast height (4.5 feet) above the ground.

Deciduous tree – A tree that loses its leaves during the winter.

Defect – The portion of a tree or log that is unusable for the intended product. Examples are decay, crook, and excessive limbiness.

Diameter – See DBH or DIB.

DIB – Diameter inside bark. Diameter of a log at its small end, measured inside the bark.

Diameter class – A tree stem diameter category that may include 1 or more inches of diameter.

Direct seeding – See seeding.

Dominant – See crown classification.

Duff – Undecomposed organic matter (such as leaves, twigs, moss, pieces of bark and wood) that litters a forest floor.

Ecosystem – A system of plants, animals, and microorganisms interacting with their environment of soil, water, and climate.

Endangered species – A plant or animal that is in danger of going extinct throughout all or part of its range.

Environment – The prevailing conditions of climate, soil, topography, and biological (other plants and animals) factors in an area.

Epicormic branch – A branch that develops by chance or from a dormant bud beneath the bark in an unusual location, usually on hardwood tree stems and major limbs. It typically arises after a stand has been heavily thinned, apparently in response to additional sunlight. Also called “water sprout.”

Even-aged stand – A stand in which the age difference between trees forming the main canopy does not exceed 20 percent of the age of the stand at maturity.

Evergreen tree – A tree that retains some or all of its leaves throughout the entire year, for example, red pine, white spruce, white-cedar.

Financial analysis – An analysis that estimates the profitability for an investment from the point of view of the decision maker(s) involved in the investment.

Foliage – Leaves on a tree or other plant.

Forb – An herbaceous flowering plant that is not a grass, sedge, or rush.

Forest – A plant community in which the dominant vegetation is trees and other woody plants.

Forest farming – The process of cultivating high value specialty crops under the protection of a forest canopy that has been modified to provide the optimal level of shade necessary for the optimum growth of selected crops.

Forest management – The process of giving a forest care so that it remains healthy and vigorous and provides the products and amenities the landowner desires; also, the application of technical forestry principles, practices, and business techniques to the management of a forest.

Forest type – A group of tree species which, because of their environmental requirements and tolerance for shade and moisture, often is found growing together. A forest type is named for one to three dominant tree species occurring in it, for example, silver maple-American elm forest type.

Forestry – The science, art, and practice of managing trees and forests and their associated resources for human benefit.

Frilling – Completely encircling the stem of a tree with ax cuts that sever the bark and cambium (actively growing layer of cells) with the intent of killing the tree. Herbicide often is injected into the frill.

Full-tree skidding – See whole-tree skidding.

Fungicide – A chemical that kills fungi.

Geotextile fabric – A very tough, coarsely-woven fabric used as underlayment for road and trail beds to strengthen the bed.

Girdling – Completely encircling the trunk of a tree with a cut that severs the bark and cambium (actively growing layer of cells) and usually penetrates into the sapwood to kill the tree by preventing the conduction of water and nutrients.

Grading (trees or logs) – Evaluating and sorting trees or logs according to wood quality.

Habitat – The local environment in which a plant or animal lives.

Haul road – A roadway that provides access for trucks to specific points in the woodland for hauling logs or other materials.

Hardboard – A panel of wood formed from wood fibers compressed together under heat.

Harden off – A natural physiological change that a plant goes through late in the growing season to prepare it for winter survival. It involves thickening of cell walls and other physiological changes.

Hardwood – A broadleaf, usually deciduous, tree such as oak, maple, ash, and elm.

Harvest – The felling and removal of final crop trees on an area to 1) obtain income, 2) develop the environment necessary to regenerate the forest, or 3) achieve objectives such as development of wildlife habitat. Contrast with intermediate cut.

Height, merchantable – The length of a tree stem from the top of the expected stump to the maximum height above which no usable wood products may be obtained. For example, if the minimum usable diameter of pulpwood sticks is 4 inches, the merchantable height of a straight tree would be its height from stump height up to a trunk diameter of 4 inches.

Height, total – Height of a tree from ground level to the top of its crown.

Herb – A nonwoody plant.

Herbicide – A chemical that kills herbaceous (nonwoody) plants. In common usage, often used interchangeably with phytocide (plant killer) and silvicide (tree killer).

Humus – any organic matter which has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries.

Increment borer – A hollow, auger-like instrument used to bore into the stem of a tree to remove a pencil-sized cylinder of wood containing a cross-section of the tree’s growth rings.

Insecticide – A chemical that kills insects.

Intermediate – See crown classification and shade tolerance.

Intermediate cut – The removal of physically or financially immature trees from a stand to improve the quality or growth of remaining trees. An intermediate cut may generate income (commercial cut) or may cost the forest landowner (a noncommercial cut). Contrast with harvest.

Kerf – The width of a saw blade. The cut made by a saw blade. The wood converted to sawdust as a saw cuts lumber from a log.

Landing – Small area in or near a woodland that is used for processing (such as sorting products, delimbing, cutting logs to shorter lengths, debarking) and loading timber products onto trucks.

Layering – Process of regenerating a tree by covering a lower branch with soil or organic matter, after which the branch develops roots and can stand alone as a new tree.

Liberation – See release cutting.

Live-crown ratio – The percentage of total tree height that has live branches on it.

Loess soil – Soil deposited by wind.

Log – A cut piece of the woody stem of a tree. A 16-foot long piece of a tree stem.

Logger – An individual whose occupation is cutting timber.

Mast – Tree-produced nuts (hard mast) and fleshy fruits (soft mast) that are edible to wildlife.

Mature tree – A tree that has reached the desired biological size or age or economic value for its intended use.

Muskeg – A bog, especially a sphagnum bog of the northern U.S., often with tussocks.

Natural forest stand – A stand of trees that originated from seed, seedlings, root suckers, or stump sprouts that were naturally present on the site.

Noncommercial cutting – A cutting that does not yield a net income, usually because the trees harvested are too small, of poor quality, or of nonmerchantable species.

Overstory – The highest horizontal layer of tree crowns in a stand of trees. Contrast with understory.

Plantation – A tree stand established by planting or direct seeding.

Planting stock – Tree seedlings or transplants that will be planted to reproduce a tree stand.

Plot – An area of land, usually less than one acre, on which trees and sometimes other vegetation are measured during a cruise (or inventory).

Pole stand – A stand of trees where DBH ranges from 4 inches up to approximately 8 to 12 inches.

Poletimber – See pole stand.

Precommercial cutting – See noncommercial cutting.

Pruning – The removal of live or dead branches from standing trees. With forest trees, pruning generally means removing limbs from the lower 17 feet of the main stem to produce higher quality (knot-free) wood.

Pulpwood – Wood cut primarily to be converted into wood pulp, chips, or fiber for the manufacture of paper, fiberboard, or other wood fiber products.

Range – 1) Commercial range is the geographic area in which a species is harvested for commercial purposes. 2) Natural range is the geographic area where a species is known to occur under natural conditions without human interference. 3) Home range is the geographic area within which a wildlife species spends most of its time throughout the year.

Reforestation – Reestablishing a stand of trees on an area where forest vegetation has been removed.

Regeneration – The process by which a stand is replaced by natural seed fall, stump sprouts, root suckers, or layering, or by artificial planting of seed or seedlings. Also, young trees.

Release cutting – A cutting operation to release seedlings or saplings from competition with other trees of the same size (a “cleaning”) or from larger and overtopping trees (a “liberation”).

Reproduction – See regeneration.

Resilience – A climate change adaptation option that enables a forested system to rebound to normal conditions after a disturbance. This option is useful with systems and species that can tolerate a wide range of environmental conditions and disturbance.

Resistance – A climate change adaptation option that protects a forested system from change. This option is useful when trying to maintain a resource with high economic, cultural, or ecological value in the short-term.

Riparian forest buffers – Strips or multiple-row plantings of trees, shrubs, grasses and forbs along rivers, streams, lakes and wetlands.

Risk – The chance of a loss. In some cases, risk can be estimated using probability principles. In other cases, the risk cannot be quantified. The terms “risk” and “uncertainty” are sometimes used interchangeably.

Root collar – The place on a tree seedling stem that differentiates the above-ground stem from the below-ground roots. The stem may be slightly swollen at the root collar.

Root sucker – A shoot that arises from a dormant bud on a lateral tree root, but grows above ground as a new tree. Root suckers usually develop when the parent tree is harvested or is severely damaged.

Roots – That portion of a tree that generally is underground and that functions in nutrient absorption, anchorage, and storage of food and waste products.

Rotation – The number of years required to establish and grow trees to a specified size, product, or maturity.

Salvage cut – Harvesting trees that have been killed or are in danger of being killed by insects, disease, fire, wind, flood or other unexpected cause to recover their economic value.

Sanitation cut – The harvesting or destruction of trees infected or highly susceptible to insects or diseases to prevent spreading the pest to remaining trees in the area.

Sapling – A small tree, often defined as being between 1 and 4 inches DBH.

Sawlog – A log large enough to produce a sawn product—usually at least 10 to 12 inches in diameter, 8 feet long, and solid.

Sawtimber – Standing trees large enough to produce sawlogs.

Scalping – Removing a patch or strip of sod to expose mineral soil in preparation for planting trees.

Scarification – Churning the soil surface to expose mineral soil and uproot vegetation to prepare a seedbed for natural or artificial seeding.

Seedbed – The ground surface on which tree seeds will naturally fall or be artificially seeded.

Seed cut – A harvest in a shelterwood system that is designed to encourage the growth of desirable seed-producing trees, create a good seedbed for germination, and eliminate undesirable trees, shrubs, and herbaceous plants that may produce seed.

Seed tree – A tree left standing after a timber harvest as a source of seed for reproducing a new stand.

Seed tree harvest – A harvest in which all trees are removed from the harvest area except for a few scattered trees that provide seed to establish a new stand. Produces an even-aged stand.

Seeding – Scattering tree seeds over an area by hand or machinery to establish a new stand of trees.

Seedling – A tree, usually defined as less than 1 inch in DBH, that has grown from a seed (in contrast to a root sucker or stump sprout).

Selection harvest – A harvest in which individual trees or small groups of trees are cut at periodic intervals (usually 8 to 15 years) based on their physical condition or degree of maturity. Produces an uneven-aged forest.

Self-prune – The ability of a tree to naturally lose its lower branches as the tree ages, thus enabling knot-free wood to grow on the stem.

Shade tolerance – Relative ability of a tree species to reproduce and grow under shade. Tree species usually are classified in descending order of shade tolerance as very tolerant, tolerant, intermediate, intolerant, or very intolerant.

Shelterwood harvest – A harvest in which trees are removed in a series of two or more cuttings to allow the establishment and early growth of new seedlings under the partial shade and protection of older trees. Produces an even-aged forest.

Shrub – A perennial plant with a persistent woody stem(s) and low-branching habit that usually grows less than 10 feet tall. Contrast with tree.

Silviculture – The art, science, and practice of establishing, tending, and reproducing forest stands of desired characteristics based on knowledge of species characteristics and their environmental requirements.

Silvopasture –  A practice where trees, livestock, and forages are intentionally managed together

Site – A contiguous (connected) area with a more or less uniform combination of biological, climatic, and soil conditions.

Site index – A measure of site quality for growing trees based on the total height that dominant and codominant trees are expected to grow in a given time period, usually 50 years in the Lake States. Trees are expected to grow taller on good sites than on poor ones in the same time period.

Site preparation – A set of practices (for example, brush clearing, chemical vegetation control, and prescribed burning) that improve a seedbed or suppress competing vegetation, to increase the chances for successfully establishing a new stand of trees.

Skid trail – Usually a temporary, unimproved roadway that enables skidders or forwarders to transport logs from the interior of a woodland to a landing.

Slash – Residue such as tree tops, branches, bark, and unmerchantable wood left on the ground after logging, pruning, or other forest operations.

Snag – A standing dead tree.

Softwoods – See conifer.

Soil texture – The particle composition of a soil based on the proportion of sand, silt, and clay.

Species – One of the basic units of biological classification—a group of organisms capable of interbreeding and producing fertile offspring.

Species composition – The mix of tree species occurring together in a stand.

Stand – A group of trees occupying a given area and sufficiently uniform in species composition, tree size distribution, stocking, and soil characteristics so as to be distinguishable from the adjoining forest. If 80 percent or more of the trees are of the same species, it is a pure stand. Otherwise, it is a mixed species stand.

Stand density – See stocking.

Stocking – A measure of the degree of crowding of trees in a stand, also known as stand density. Commonly expressed by the number of trees per acre or percentage of crown cover.

Stocking chart – A chart usually based on one or more tree species, number of trees per acre, and tree stem diameters that shows the best stocking for timber growth, considering the species present and stem diameters.

Stratify seed – Subjecting seed to cold temperatures and regulating moisture for a period of time to break seedcoat dormancy and improve seed germination.

Structural board – A wood panel made from chips or flakes that have been formed into a panel by heat, pressure, and sometimes an adhesive. Frequently used in construction for underlayment on floors, roofs, and walls.

Stumpage – The dollar value of a standing tree or group of trees.

Stump sprout – A young tree that has grown from a dormant bud on a tree stump. It is an exact genetic replica of the original tree.

Succession – The process by which one plant community is gradually replaced by another due to environmental conditions and species characteristics, such as shade tolerance.

Sucker – See root sucker.

Suppressed – See crown classification.

Sweep – A C-shaped curvature in a tree stem or log.

TSI (Timber Stand Improvement) – The practice of removing undesirable trees, shrubs, vines, or other vegetation to achieve the desired stocking of the best quality trees.

Thinning – Cutting scattered trees or rows of trees to reduce the stocking and concentrate growth on fewer, higher quality remaining trees.

Threatened species – A plant or animal that may soon become endangered throughout all or part of its range.

Till – Unstratified glacial drift consisting of clay, sand, gravel, and boulders intermingled.

Timber – Standing trees, usually of commercial size.

Timber inventory – A collection of information about a stand made by measuring tree and stand characteristics such as tree volume and grade and stand density.

Tolerance – See shade tolerance.

Tract – A contiguous (connected) area of land (and water).

Transition – A climate change adaptation option that actively encourages forest change for long-term success. This option is useful in highly vulnerable forested systems or when resistance and resilience actions may be too risky.

Transplant – A tree seedling that was transplanted at least once in the nursery.

Tree – A woody plant with a well-defined stem and a more or less definitely formed crown, which usually grows more than 10 feet tall.

Tree farm – A privately owned woodland dedicated to the production of timber crops and other environmental benefits. It may be formally recognized by the Tree Farm program of the American Forest Council.

Tree length skidding – When a tree is felled, the process of removing the top and limbs, then moving (skidding) the entire tree stem in one piece to the landing.

Trunk – The main stem or bole of a tree.

Understory – A low-growing, horizontal layer of woody or herbaceous vegetation that forms beneath an overstory of taller trees.

Uneven-aged forest – A forest or stand in which there are more than two age classes of trees present. There usually is a minimum age difference of 20 percent of the rotation length in years.

Veneer – Thin sheets of wood (usually less than 1 /4-inch thick) produced by slicing or peeling a log. A tree or log suitable for cutting into veneer because of its species, size, and good quality.

Volume table – A table that estimates the volume of wood in a standing tree (cords or board feet), usually based on DBH and merchantable height.

Vulnerability –  The susceptibility of a system to adverse effects, notably from from climate change. A woodland might be considered to be vulnerable if it is at risk of significant composition change or substantial declines in health or productivity.

Water table – The highest point in a soil profile at which water saturates the soil on a seasonal or permanent basis.

Weeding – The practice of removing undesirable tree species that take up valuable growing space in a stand.

Whole-tree (full-tree) skidding – The process by which an entire tree, including the stem, limbs, and top, is brought to the landing in one piece.

Whorl (of branches) – A set of branches arising from one year’s growth that occur at the same height on a tree stem and are distributed around the stem at relatively even spacing.

Windbreaks – Plantings of single or multiple rows of trees, shrubs or grasses that protect crops, livestock, and wildlife from wind’s harmful consequences.

Windthrow – A tree uprooted or broken by wind.

Wolf tree – A tree with a large crown, but poor form and low wood product value that occupies more space in the forest than its timber value justifies.

Wood pulp – Mechanically ground or chemically digested wood used in the manufacture of paper.

Woodland management – See forest management.