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B
BARE-ROOT SEEDLING: Tree
seedling grown in a nursery bed. When large enough for transplanting,
the seedling is lifted from the nursery bed, and the dirt is removed from
the roots before packaging.
BASAL AREA: The
cross-section area of the stem or stems of a plant - or of all plants
- in a stand, generally expressed as square units per unit area. Tree
basal is used to determine percent stocking. For shrubs and herbs, it
is used to determine phytomass. Grasses, forbs, and shrubs usually measured
at, or less than, 1 inch above soil level. The basal area for trees is
the cross-section area of a tree stem in square feet, commonly measured
at breast height (4.5 feet above ground) and inclusive of bark, usually
computed by using d.b.h. or tallied through the use of basal area factor
angle gauge.
BEDDING: Land
prepared before planting in the form of small mounds. The prepared land
concentrates topsoil and elevates the root zone of seedlings above temporary
standing water. Fertilizer is often incorporated into the bedding.
BOARD FOOT: A
unit of wood measuring 144 cubic inches. A 1-inch by 12-inch shelving
board that is 1 foot long is equal to 1 board foot. Board foot volume
is determined by: length (feet) x width (inches) x thickness (inches)
divided by 12.
BUFFER STRIP: A
narrow zone or strip of land, trees, or vegetation bordering an area.
Common examples include visual buffers, which screen the view along roads,
and streamside buffers, which are used to protect water quality. Buffers
may also be used to prevent the spread of forest pest.
C
CAMBIUM: Layer of living cells between
the wood and the innermost bark of a tree. Each growing season the cambium
adds a new 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.
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.
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. See also REGENERATION CUT
and SALVAGE CUT.
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.
CONIFER: Tree that is a gymnosperm,
usually evergreen, with cones and with needle-shaped or scale-like leaves,
producing wood known commercially as softwood.
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.
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 less than 4 feet.
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 that
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 or 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. 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 growths in a tree crown to admit light, reduce weight, and lessen
wind resistance.
CRUISE: A survey of forestland to
locate timber and estimate its quantity by species, products, size, quality,
or other characteristics.
D
D.B.H.: Diameter
at breast height.
DEBARKER: (a) Machine for removing
bark from logs or bolts. (b) Machine used to remove the bark from roundwood
prior to processing into chips, lumber, or other wood products.
DECIDUOUS: Perennial plants that are
normally leafless for some time during the year.
DIAMETER AT BREAST HEIGHT (d.b.h.):
Tree d.b.h. is the outside bark diameter at breast height. Breast height
is defined as 4.5 feet (1.37 meters) above the forest floor on the uphill
side of the tree. For the purposes of determining breast height, the forest
floor includes the duff layer that may be present, but does not include
unincorporated woody debris that may rise above the ground line.
DIAMETER CLASSES: Classification of
trees based on the diameter of outside bark measured at d.b.h. In forest
surveys, each diameter class encompasses approximately 2 inches: the 6-inch
class would include trees 5.0 through 6.9 inches in d.b.h.
E
ECOLOGY: The science or study of the relationships between
organisms and their environment.
EVEN-AGED MANAGEMENT: A forest management
method in which all trees in an area are harvested at one time or in several
cuttings over a short time to produce stands that are all the same age
or nearly so. This management method is commonly applied to shade-intolerant
conifers and hardwoods.
F
FIREBREAK: Any nonflammable barrier
used to slow or stop fires. Several types of firebreaks are mineral soil
barriers; barriers of green, slow-burning vegetation; and mechanically
cleared areas.
FOREST: Area managed for the production
of timber and other forest products or maintained as wood vegetation for
such indirect benefits as protection of catchment areas or recreation.
FORESTATION:
Establishment of a forest, naturally or artificially, on an area,
whether previously forested or not.
FORESTLAND: Land at least 10% stocked
by trees of any size or formerly having had such tree cover and not currently
built up or developed for agricultural use. Forestland may include Grassland,
Shrubland, Treeland, Wetland, and/or Barren land. Examples of forestland
use are grazing, recreation, and timber production. See also LAND USE
CLASS.
FOREST MANAGEMENT: (a) Proper care and
control of wooded land to maintain health, vigor, product flow, and other
values (soil condition, water quality, wildlife preservation, and beauty)
in order to accomplish specific objectives. (b) The practical application
of scientific, economic, and social principles to forest property.
FOREST STEWARDSHIP PROGRAM: A cooperative,
technical-assistance program designed to encourage multiple resource management
on private forestland. Emphasis is placed on preharvest planning to enhance
and protect forest-based resources. Authorized under the 1990 Farm Bill,
the program is based on national guidelines but is set by individual states.
G
H
HARDWOODS or DECIDUOUS TREES: Trees
with broad, flat leaves as opposed to coniferous or needled trees. Wood
hardness varies among the hardwood species, and some are actually softer
than some softwoods.
I
INCREMENT BORER: Tool used to take
a small core from the bole of a tree to determine growth rate.
J
K
L
LAND USE CLASS: The predominant purpose
for which an area is employed. Classes include Agricultural Land, Forestland,
Rangeland, Wetland, Urban/Suburban, and Utility/Transportation Corridors
(Roads, Railroads, and Utility Corridors).
LOG RULE or LOG SCALE: A table based
on a diagram or mathematical formula used to estimate volume or product
yield from logs and trees. Three log rules are used today in North Carolina:
Scribner is the common scale for pine; Doyle is the common hardwood scale;
and the International 1û4" Rule best measures mill output, although
it is used less frequently than the other log scales.
M
MBF: Abbreviation denoting 1,000 board
feet. MBF is a typical unit of trade for dimension lumber and sawtimber
stumpage. Note: It takes 11 MBF of wood to build an average 1,900-square-foot
house.
MERCHANTABLE: Logs exceeding a minimum
size and a minimum usable volume that are suitable for sale.
MIXED STAND: A timber stand in which
less than 80% of the trees in the main canopy are of a single species.
N
NATURAL REGENERATION: A stand of trees
grown from natural seed fall or sprouting.
O
OVERSTORY: Layer of foliage in a forest
canopy, including the trees in a timber stand. Tall mature trees that
rise above the shorter immature understory trees.
P
PAY-AS-CUT: Timber purchase based
on a dollar amount for a certain amount/volume of wood, such as dollars
per MBF. Payment is made only as timber is cut and transported.
PRECOMMERCIAL THINNING: Cutting trees
from a young stand so that the remaining trees will have more room to
grow to marketable size. Trees cut in a precommercial thinning have no
commercial value, and normally none of the felled trees are removed for
utilization. The primary intent is to improve growth potential for the
trees left after thinning.
PRESCRIBED or CONTROLLED BURN: The
use of fire under specific environmental conditions to achieve forest
management objectives. Used to reduce hazardous fuel levels, control unwanted
vegetation, favor desired vegetation, and improve visibility and wildlife
habitat.
Q
R
REFORESTATION: Reestablishing a forest
by planting or seeding an area from which forest vegetation has been removed.
REGENERATION CUT: A cutting strategy
in which old trees are removed, while favorable environmental conditions
are maintained for the establishment of a new stand of seedlings. See
also SALVAGE CUT and CLEAR-CUT THINNING.
S
SALVAGE CUT: The harvesting of dead
or damaged trees - or of trees in danger of being killed by insects, disease,
flooding, or other factors - in order to save their economic value. See
also REGENERATION CUT and CLEAR-CUT THINNING.
SAWLOG or SAWTIMBER: A log or tree that is large enough (usually
10 to 12 inches in diameter) to be sawed into lumber. Minimum log length
is typically 8 feet.
SCRIBNER RULE: Diagram log rule, one of the oldest in existence,
that assumes 1-inch boards and a 1û4-inch kerf, makes a liberal allowance
for slabs, and disregards taper.
SEALED BID SALE: Sale in which interested
parties submit written bids at the time and place specified.
SEEDLING: (a) A tree, usually less
than 2 inches diameter at breast height, that has grown from a seed rather
than from a sprout. (b) A nursery-grown tree that has not been transplanted
in the nursery.
SELECTION SYSTEM: Uneven-aged silvicultural system in which
single or small groups of trees are periodically selected to be removed
from a large area so that age and size classes of the reproduction are
mixed.
SILVICULTURE: The art, science, and practice of establishing,
tending, and reproducing forest stands of desired characteristics. It
is based on knowledge of species characteristics and environmental requirements.
SITE INDEX: Height of a tree at a specified index or base age.
Used as an indicator of site quality.
SITE PREPARATION: Preparing an area of land for planting, direct seeding,
or natural reproduction by burning, chemical vegetation control, or by
mechanical operations such as disking, bedding, scarifying, windrowing,
or raking.
SOFTWOOD or CONIFER: A tree belonging
to the order Coniferales. Softwood trees are usually evergreen, bear cones,
and have needles or scale-like leaves. They include pine, spruce, fir,
and cedar trees.
SPECIES: A group of related organisms having common characteristics
capable of interbreeding. Loblolly and Virginia pine are common species
that can be interbred.
STAND: An easily defined area of the
forest that is relatively uniform in species composition or age and can
be managed as a single unit.
STAND AGE: The mean age of the dominant
and codominant trees in the stand.
STOCKING: A description of the number of trees, basal area, or volume
per acre in a forest stand compared with a desired level for balanced
health and growth. Most often used in comparative expressions, such as
well stocked, poorly stocked, or overstocked.
STREAMSIDE MANAGEMENT ZONE (SMZ): An area adjacent to a stream
in which vegetation is maintained or managed to protect water quality.
The width depends on slope, but 50 feet is the normal minimum. Trees may
be removed from SMZs as long as the streambed is not disrupted and sufficient
vegetation is left to protect water quality.
STUMPAGE: The value or volume of a tree or group of trees as
they stand uncut in the woods (on the stump).
SUSTAINED YIELD: Management of forestland to produce a relatively
constant amount of wood products, revenue, or wildlife. See also YIELD.
T
TARGETED/TIMBERLAND INVESTMENT STRATEGIES or TTIS : TimberVest's
process of analyzing, investing, managing, and liquidating investments
along timberland's biological yield curve in order to construct portfolios
that achieve the investor's target return objectives.
THINNING: A tree removal practice that reduces tree density
and competition between trees in a stand. Thinning concentrates growth
on fewer, high-quality trees; provides periodic income; and generally
enhances tree vigor. Heavy thinning can benefit wildlife through the increased
growth of ground vegetation. See also PRECOMMERCIAL THINNING.
TIMBER APPRAISAL: Economic appraisal of the monetary value
of a timber stand.
U
UNDERSTORY: (a) The layer formed by
the crowns of smaller trees in a forest. (b) The trees beneath the forest
canopy. (c) Foliage layer beneath the forest canopy. (d) Young trees that
are growing beneath the tall mature trees in a timber stand.
UNEVEN-AGED MANAGEMENT: Silvicultural system in which individual
trees originate at different times and result in a forest with trees of
all ages and sizes. Harvest cuts are on an individual-tree selection basis.
V
W
X
Y
YIELD: (a) Amount of product output
recovered from a quantity of raw material input in forest product industries.
(b) Estimate in forest menstruation of the amount of wood that may be
harvested from a particular type of forest stand by species, site, stocking,
and management regime at various ages.
YIELD CURVE: A representation of stand volume, usually as a
function of stand age, in graphical or tabular form.
Z
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