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adaptive management feedback - the ability to generate meaningful effectiveness monitoring data and use it to make ongoing project and program adjustments where required.

alluvial - (see fluvial).

biogeoclimatic classification - a hierarchical classification system of ecosystems that: integrates regional, local, chronological factors, and combines climatic, vegetation, and site factors (Meidinger and Pojar 1991).

biogeoclimatic zone - a large geographic area with a broadly homogeneous macroclimate. It has characteristic webs of energy flow and nutrient cycling and typical patterns of vegetation and soil (Meidinger and Pojar 1991). Refer to Appendix 3 for biogeoclimatic zones of BC.

channel - a waterway of discernible extent that continuously or periodically contains moving water, and has a defined bed and banks.

climax community - the final and relatively stable stage in plant succession for a given environment where the species present perpetuate themselves in the absence of disturbance.

coarse woody debris (CWD) - sound and rotting logs and stumps that provide habitat for small terrestrial animals and their predators. Large woody debris is one type of CWD, but with a primarily aquatic rather than terrestrial influence.

canopy - the overhead branches and leaves of vegetation.

fish habitat - spawning grounds and nursery, rearing, food supply and migration areas on which fish depend directly or indirectly in order to carry out their life processes. Habitat can be located instream (main river or stream system) or off-channel (small tributaries or wet areas; includes off-channel and instream habitat).

floodplain - areas of flat land bordering a watercourse. They are frequently at or near the same elevation as the top of the streambanks and are subject to flooding.

fluvial - refers to materials transported and deposited by running water.

Forest Practices Code (Code) - specifies planning and operational guidelines for each phase of timber harvesting operations around streams, lakes and wetlands in the province of British Columbia.

free growing - a term used to describe a stand of trees that has grown sufficiently above the grass and shrub level, ensuring its survival (and free growth) against competition from other vegetation.

gully - a long, linear depression incised into steep hillslopes, where the overall gradient is at least 25%, with a channel confined in a V-notch ravine with banks higher than 3 m, sideslopes steeper than 40%, and an overall length greater than 100 m.

intermittent stream - stream with a defined channel, but dry for periods of the year, usually the late summer and fall period of low precipitation and no snowmelt.

large woody debris (LWD) - pieces of dead wood, having a diameter of 10 cm or larger over a minimum 2 m length, that intrudes into the stream channel; important for providing fish habitat and in influencing channel morphology.

mesic - intermediate or medium moisture conditions; that is, neither very wet nor very dry. The term refers to habitats that have neither an excess nor a shortage of water, relative to the existing extremes in a given area.

nurse-tree shelterwood - a nurse-tree shelterwood system manages different species in two different layers. The tree canopy shelters and provides a more suitable environment for establishment and juvenile growth of the young regeneration. The overstorey can be gradually removed, or removed all at once when the regeneration is developed enough to withstand open site conditions. Where applicable, this system enables shade-intolerant and shade-tolerant tree species to be managed on the same site for a period of time. An example of this is the managing of a redcedar understorey with a cottonwood or alder overstorey.

overstorey - all trees growing in a forested ecosystem, regardless of height or trunk size.

perennial stream - a stream that has flowing water all year.

rehabilitation - returning to a state of health and useful activity. In this manual, rehabilitation means producing conditions more favourable to particular groups of organisms, especially the economically-valuable or aesthetically-desired components of the native flora and fauna, without necessarily returning the system to its undisturbed condition.

restoration - bringing back to a former or original condition (e.g., the pre-logging state). In this manual the term restoration is meant to include rehabilitation.

riparian area - an area of land adjacent to a stream, river, lake or wetland, containing vegetation that, due to the presence of water, is distinctly different from the vegetation of adjacent upland areas.

riparian management areas (RMA) - areas around streams and wetlands that consist of a riparian management zone, and where required by the regulations, a reserve zone within which constraints to forest practices are applied. Its width is determined by the class of stream or wetland. Refer to tables 1 and 2 in the Riparian Management Area Guidebook.

riparian management zone (RMZ) - the zone within the RMA and outside the riparian reserve zone where limited harvesting is permitted. As with the RRZ, its width is determined by the class of stream or wetland. Refer to tables 1 and 2 in the Riparian Management Area Guidebook.

riparian reserve zone (RRZ) - the zone within the RMA immediately bordering the stream or wetland where no timber harvesting is permitted. Its width is determined by the class of stream or wetland. Refer to tables 1 and 2 in the Riparian Management Area Guidebook.

riparian vegetation type (RVT) - classification of vegetation based on stand structure and species composition.

riparian zone - land adjacent to the normal high water line in a stream, river, lake or pond and extending to the portion of land influenced by the presence of the adjacent ponded or channeled water.

silviculture - managing forest vegetation by controlling stand establishment, growth, composition, quality and structure, for the full range of forest resource objectives.

silviculture prescription (SP) - a site-specific plan that describes the forest management objectives for an area. SPs must be consistent with any higher level plan that encompasses the area to which the prescription applies. The SP prescribes the method for harvesting the exisiting forest stand, and a series of silviculture treatments that will be carried out to establish a free growing (above brushline) crop of trees in a manner that accommodates other resource values identified. Subsequent documents, including cutting authorities and logging plans, must follow the intent and meet the standards stated in the SPs.

site series - a method of site classification defined by using late seral or climax vegetation within a biogeoclimatic subzone. Each site series is given a two-digit numeric code that relates to its position on the relative moisture and nutrient scales. This term forms the basis of much of the MOF field guides for site identification and interpretation in forest regions (see MOF Land Management Handbook references in References section).

small organic debris (SOD) - organic material such as leaves, detritus, terrestrial insects, twigs that enter the stream and become part of the aquatic food chain.

snags - standing dead trees that provide essential habitat for wildlife.

soil horizon - a layer of soil that is distinguished from adjacent layers by characteristic physical properties such as structure, colour or texture. The letters A, B and C are used to designate soil horizons. The A horizon is the upper part (usually organic) and is the zone of leaching minerals and nutrients. The B horizon lies under the A and consists of weathered material with accumulated minerals and nutrients. The C horizon under the B is the layer of unconsolidated, weathered parent material. Not all horizons are present in all soils.

stand management prescription (SMP) - a site-specific plan describing the nature and extent of silviculture activities planned for a free growing stand of trees to facilitate the achievement of specified or identified social, economic and environmental objectives. An SMP was created under the Code to complement the silvilculture prescription by specifying a full-rotation plan or strand strategy for an individual stand.

stand structure - the vertical arrangement and stocking of trees within individual crown classes (canopy layers) in a stand.

Stand structure descriptions:

INIT: Initial stage - as per shrub-herb below, but the very initial stage after disturbance. Bryophytes, lichens and herbaceous plants are dominant.

SH: Shrub-herb - this stage develops after a disturbance in which the forest canopy is completely or significantly removed (e.g., after clearcut logging or a severe fire) and typically lasts up to 15-20 years, although it may persist much longer. The vegetation is characterized by the dominance of shrubs and herbs; young trees are also abundant, although not dominant. Establishment is the primary process; biomass increases rapidly and floristic diversity is often high. This stage is also often referred to as the regeneration stage.

PS: Pole-sapling - this stage typically begins 5 to 15 years after a disturbance, depending on the tree species, when the young trees overtop the shrubby or herbaceous vegetation. Saplings are the earlier stage, poles the later. It usually lasts for up to 30 to 40 years, but may persist indefinitely - as in the case of some lodgepole pine stands in the interior. Trees at this stage are characterized by their vigourous growth and lack of dead lower branches. Stands are more or less even-aged, having been planted or established naturally within a relatively short time. Establishment remains the dominant process, with stand biomass continuing to increase. Understorey biomass declines as the canopy closes in. Note, in some text books the pole stage is the young forest stage.

YF: Young forest - this stage begins when self thinning becomes evident. A second cycle of trees begin to show a significant presence in the ground layer by the end of this stage. Differentiation of the initial tree species into dominant, co-dominant and suppressed layers, and self-thinning, low stand diversity and increasing biomass through rapid height growth are characteristic of this stage. Understorey development is often limited by the dense forest canopy. This stage usually starts about 30 to 40 years after a succession-initiating disturbance and lasts for up to 50 years. In open forests where self-thinning may not be evident and a second cycle of trees is lacking, this stage will be characterized more by the vigourous growth of the trees.

MF: Mature forest - this stage extends until the initial trees mature, height growth slows, and some of the initial trees begin to die. A second cycle of trees may show a significant presence in the lower tree layers. In some cases, the first cycle of trees may begin to die from old age before significant development of a replacement layer begins; in other cases, the next cycle of trees may be well developed before significant mortality of the initial trees occurs. Generally, the even age distribution typical of early stages changes as new trees become established and older trees begin to die. Gap phase replacement may begin to be important at this stage. The understorey re-develops as the canopy opens.

OG: Old growth - old-growth stands generally have an all-age class distribution. Growth slows and volume is lost through rot. Stands show structural heterogeneity as gaps develop in the canopy after trees fall. The understorey biomass increases as light becomes available. The presence of dead wildlife trees and rotting logs scattered on the forest floor enhances the value of forests at this seral stage for wildlife.

stream- the watercourse formed when water flows between continuous definable channel boundaries. Flow in the stream channel may be perennial or intermittent.

stream class - method of classifying streams based on size, gradient and presence of fish. The classification system is based on the Code and ranges from S1 to S6. See Table 1 in text for breakdown of classification.

stream reach - relatively homogenous section of a stream having a sequence of repeating structural characteristics (or processes) and fish habitat types.

streamside - the land, and the vegetation it supports, immediately in contact with the stream or sufficiently close to it to have a major influence on, or to be influenced by, its ecological character.

succession - the gradual change that occurs in the vegetation of a given area of the earth's surface, or when one community succeeds the other.

understorey - shrubs (< 2 m in height), herbs or mosses growing in a forest.

watershed - the land on which water falls from the atmosphere and moves downslope to other locations. Each watershed is a catchment area divided from the next watershed by topographic features, most noticeably ridgetops. Watersheds are the natural landscape units from which hierarchical drainage networks are formed.

wetland - a swamp, marsh or other similar area that supports natural vegetation that is distinct from the adjacent upland areas. More specifically, a wetland is an area where a water table is at, near, or above the surface or where soils are water-saturated for a sufficient length of time that excess water and resulting low oxygen levels are principal determinants of vegetation and soil development.

wildlife tree - a standing dead or live tree with special characteristics that provide valuable habitat for the conservation or enhancement of wildlife.

windthrow - where trees are blown over due to wind conditions, in situations where harvest of adjoining forest has resulted in loss of wind protection within the remaining forest. Trees in narrow riparian buffer strips can be susceptible to windthrow conditions, especially in areas of high winds and water saturated soils.

xeric - dry moisture conditions.

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