General Terms

Advance Regeneration – seedling or saplings that develop naturally in the understory (under older, taller trees).

Age Class – one of the intervals, e.g. 10-year age class, into which the age range of trees is divided for classification or use.

Age Class Distribution – the proportionate representation of different age classes in a forest.

AAC – annual allowable cut

Allowable Cut – the volume of timber that may be harvested during a period (usually a year) that is specified by a sustained yield forest plan.

Allowable Cut Effect – the allocation of anticipated future timber yields to the present allowable cut.  Note: the allowable cut effect is employed to increase current harvest levels by spreading future growth over all the years in a rotation.

Blowdown/Windthrow - the natural process of trees being blown over.  Sometimes we can economically locate, harvest and sell those trees, sometimes we cannot.

C.F.I. – Continuous Forest Inventory.  A form of forest sampling designed to discover significant changes with time, particularly growth and mortality patterns.

Chance - an area designated for harvest

Concentration Yard - an area designated for the collection of trees to be carefully sorted, prepared, and subsequently sold the best possible market

Cord, Ton, Thousand Board Feet - units used to measure a volume of wood

Crop Tree - the best trees in a stand that we want to focus unhindered growth and subsequent increase in volume and value on.

Decay - the natural breakdown of plant matter by fungi and other organisms into simple materials.

Forest Type – a class of forest stands defined by composition, structure or age, for management purposes.

Forest Succession – a gradual supplanting of one community of plants with another; seedlings – saplings – poles – sawtimber.

Fragmentation – the process by which a forest is broken into small islands of mature stands within a landscape of younger stands.  Fragmentation is a concern because of the effect of noncontiguous forest cover on the movement and dispersal of animals in the landscape.

Hardwood - trees with leaves instead of needles, Maple, Birch, Poplar

Harvest Prescription - a planned series of harvest treatments designed to achieve certain goals or conditions in a forest area

Immature Forests - a young forest not yet suitable for production of forest products

Intolerant Hardwood - hardwood trees that prefer to grow in full sunlight, i.e. Birch

Mature Forests - a forest stand that has achieved most of its potential growth

Mean Annual Increment (MAI) – the total volume of a tree, or forest stand, divided by its’ total age.  If a stand contains 30 cords/acre and is 60 years old, its’ MAI is 30 cords/acre divided by 60 years or .5 cords/acre/year.

Mixedwood - a forest composed of both hardwood and softwood

Natural Regeneration - new young trees grown naturally from the seed of nearby trees

Overstory – the uppermost forest canopy layer.

Partial Cut - a general term used to describe any harvest that removes only some of the trees, like thinning or shelterwood preparatory cuts

Photosynthesis - process by which green plants use the energy of light to convert carbon dioxide and water into the simple sugar glucose. Photosynthesis provides the basic energy source for virtually all organisms. An extremely important byproduct of photosynthesis is oxygen, on which most organisms depend.

Renewable - the careful use of a naturally sustained resource that does not diminish future characteristics or values

Residual (stand) (tree) (stocking) – those remaining after an intermediate or partial cutting.

Riparian Zone – a terrestrial area adjacent to, and influenced by, a perennial body of water.  Riparian zones provide a functional link between terrestrial and aquatic ecosystems through coarse and fine organic matter input, bank stability, water temperature regulation, sediment and nutrient flow regulation, and maintenance of unique wildlife habitat.

 Rotation – the period between regeneration establishment and final cutting.  Rotation may be based on size, age, or culmination of growth.

Seral Stage – a temporal and intermediate stage in forest succession.

Silviculture – the art and science of controlling the establishment, growth, composition, health, and quality of forests to meet the diverse needs of landowners and society on a sustainable basis.

Silvicultural System(s) – a planned series of treatments for tending, harvesting and re-establishing a stand.  A more complete explanation is included after the glossary.

Softwood - trees with needles instead of leaves, Spruce, Fir, Pine, and Cedar

Sound - forest products without defect.

Stand – a contiguous group of trees sufficiently uniform in composition and structure to be a distinguishable unit. 

Stocking – the number of trees in a given area, particularly in relation to what is optimum.

Sustainable Forestry - the care and use of forests and forest land in a way, and at a rate that maintains all of the plant, animal and human capacity and values for now and the future

Temporal – as used here, the pattern of harvest activity over time in a given area.

Tolerant Hardwood - hardwood trees that grow well in shade, i.e. Maple

Transpiration - the process that removes excess water from plants by evaporation through openings in the leaves.

Understory – all forest growth growing under an Overstory.

Vernal Pool – a temporary, seasonal, semi permanent body of water that is essential breeding habitat for certain amphibians and invertebrates.

Wildlife Tree – a live or dead tree designated for wildlife habitat or retained for future wildlife habitat.

Yard - the roadside area where trees from a harvest will be stored until put on trucks.