Forestry Terms - G -
GEOLOGIC FEATURES: Landforms or other features of significant geologic interest that may require special management to: (1) protect the special qualities, or (2) provide interpretation to the public.
GEOLOGIC FORMATION: A mappable body of rock identified by distinctive characteristics, some degree of internal homogeneity, and stratiographic position. The name normally consists of two parts. The first is the name of the geographic locality where the formation was first identified and described. This is followed by a descriptive geologic term, usually the dominant rock type.
GEOLOGIC HAZARDS: A natural condition that poses some risk to human health or safety.
GEOLOGIC TIME UNIT: A division of time traditionally distinguished on the basis of observable changes in worldwide life forms as represented in the fossil record in sedimentary rocks.
GIN POLE -Erect pole with guys, 30 to 50 feet in height, leaning so that a loading
block hung at the top is directly over the point
where the truck will be spotted for loading.
GIRDLING - A physical cutting or disruption of the cambial sap flow within a tree. Girdling by humans, animals, or insects can often kill a tree.
GLIDES: A third general habitat category possessing attributes of both riffles and pools. Glides are characterized by moderately shallow water (10-30 cm deep) with an even flow that lacks pronounced turbulence. Although they are most frequently located at the transition between pool and the head of a riffle, glides are occasionally found in long, low gradient stream reached with stable banks and no major flow obstructions. The typical substrate is gravel and cobbles.
GRADE -Established quality or use classification of timber.
-Slope of a surface, such as a roadway.
-The elevation of a real or planned surface or structure.
-Completed base for a road.
-To reduce ground to a level or sloped surface.
GRADIENT -Amount by which the grade increases or decreases in a unit of horizontal distance.
GRAPPLE -Hinged mechanism capable of being opened an-d closed; used to grip logs during
yarding or loading.
-Hinged set of jaws, capable of being opened and closed, used to grip logs during yarding or loading .
-Hydraulically operated arms, used to either lift and load, or lift and skid, trees. May be of the following types: swivel,
stationary, self-centering, parallelogram, or bunk
GRASS: A plant in the family Gramineae.
GRASS-LIKE PLANT: A plant which resembles grasses, but belongs to the families cyperaceae (sedges) and Juncaceae (rushes).
GRASSLAND: Areas on which vegetation is dominated by grasses, grass-like plants, forbs, and/or cryptogams (mosses. lichens, and ferns), provided these areas do not qualify as Built-up land or Cultivated cropland. Examples are tall grass and short grass prairies, meadows, cordgrass marshes, sphagnum moss areas, pasture lands, and areas cut for hay.
GREEN TREE RESERVOIR (GTR) - A wooded area that has been intentionally flooded to benefit migratory ducks and waterfowl. GTRs may be planted with a grain crop, such as millet, the summer before the winter flooding. The GTR can be an effective, low-cost method of luring waterfowl into forested tracts.
GREEN STRIP -Uncut strip of timber left along streams and roads. Also known as buffer
strip, leave strip, streamside
GROUND WATER AQUIFERS: A geologic formation that is sufficiently permeable to conduct ground water and has the potential to yield economically significant quantities of water to wells and springs.
GROUP SELECTION - (a) The removal of small groups of trees to regenerate shade-intolerant trees in the opening (usually at least 1/4 acre). (b) A specific type of selective cutting.
GROWTH -Increase in diameter, basal area, height, and volume of individual trees or stands during a given period of time. Also known as increment.
GYPPO (gypo) -Independent logger who usually runs small-scale logging
-a small, independent sawmill or other wood related operation.
-personnel paid on piecework basis, such as a "gyppo" car loader or a "gyppo" trucker