Forestry Terms - I -
IMPOUNDMENT: A body of water held back by a dam, dike, floodgate or any other barrier. All artificially ponded water, including natural bodies of water with artificially controlled water levels, except that captured directly as it falls from the atmosphere.
IMPROVEMENT CUT - An intermediate cut made to improve the form, quality, heath, or wildlife potential of the remaining stand.
INCENTIVE - A reward for improving forest management. Incentives include reimbursement of some expenses but can also take the form of an abatement of property or income tax.
INCREMENT - SEE GROWTH
INCREMENT BORER -Tool used to take a small core from the bole of a tree to determine growth rate
INSTREAM COVER: The amount of vegetation and organic debris within a stream channel capable of providing protection for fish.
INSTREAM WOODY DEBRIS: A measure of the amount, size and arrangement of woody material in a stream.
INTENSIVE FOREST MANAGEMENT -Utilization of a wide variety of silvicultural practices, such as planting, thinning, fertilization, harvesting, and genetic improvement, to increase the capability of the forest to produce fiber.
INTERMEDIATE TREES: Trees or shrubs receiving little direct light from above, and none from the sides; usually with small crowns considerably crowded on the sides that are generally either below or extending into the canopy formed by codominant trees or shrubs.
INTERNATIONAL LOG RULE -Formula rule that allows a 1/2 inch taper for each
4 feet of length and allows for a 1/16-inch shrinkage for each inch of board thickness.
Rule used by the USDA Forest Service.
INTERNATIONAL 1/4 INCH SCALE -Log scale modification of an earlier rule using a 1/8-inch
kerf, based on an analysis of the loss ofwood fiber incurred in the conversion of saw logs
to lumber. One of the few rules incorporating a basis for dealing with log
taper.
INTOLERANT -Tree relatively incapable of developing and growing normally in the shade of,
and in competition with, other trees.
