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...and low. This is done by feathering edges, protecting/ cultivating understory trees, concentrating retention trees along edges, and rapid regeneration of the cut areas (Harris 1984; Chen et al. 1995; =-=Oliver & Larson 1990-=-). Untreated stands Untreated stands remain in the stem exclusion stage longer than thinned stands. The high competition and low light penetration into these stands will result in low crown ratios and...

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...l provide shade levels equivalent to mature stands in 10 years (Summers 1982 cited in Skaugset 1992). Another study showed 50% of a Coast Range stream shaded within 5 years of harvesting and burning (=-=Beschta et al. 1987-=-). Our knowledge on the effect of shade on water temperature is based on comparing stream temperatures under forested conditions to a denuded state. It is also based on research to establish how wide ...

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...ended sediment concentrations, though often at a substantial cost (Brazier; Brown 1973). Sources of sediment from surface erosion are soils exposed by broadcast burning, and along roads and landings (=-=Beschta 1978-=-). Beschta also noted in the Alsea Study that high-lead cable logging, light broadcast burning (in contrast to extremely hot burns) had little affect on sedimentation, and the retention of streamside ...

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...rstory structure. Wind may reach deep into a stand where tree branches are high and the understory sparse, and may penetrate only a short distance where the canopy is continuous and understory dense (=-=Chen et al. 1995-=-). Chen (1991) found edge influence into old-growth stands on biological variables varied dramatically from essentially none to up to 450 feet for small (0-10 cm) hemlock seedlings. See the discussion...

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...06 39 89 35 71 27 53 21 Yrs. of growth required for before the new stand blocks gap created clearcutting. 120 192 115 47 96 38 77 30 58 23 Note: The height age relations from Kings site index tables (=-=King 1966-=-). Stand ages are assumed to be age at breast height, from the Kings Tables, plus 4 years. The site index used is 126. Chen (1991) reported the area of edge influence, into old-growth stands, for the ...

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...90). Prior to the post World War II economic development, forest harvest occurred on a fairly small scale, taking individual trees or small groups of trees and not affecting large blocks of habitats (=-=FEMAT 1993-=-). Many of the current conditions are from the variation of management between the landowners throughout the watershed. Problems with productivity are explained in the other resource sections (i.e. si...

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...te as an active zoospore or resting chlamydospore. The spread of the disease requires precise conditions of cool soil temperatures and saturated to near saturated soil moisture over a period of time (=-=USDA, 1994-=-). Infection is highly dependant on the presence of free water in the vicinity of susceptible tree roots. High risk areas are stream courses, drainages, or low lying areas downslope from infected area...

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...ng from forest roads was the most important source of increased stream sedimentation, whereas soil disturbance caused by logging operations resulted in no detectable increase in stream sedimentation (=-=Fredriksen et al. 1973-=- cited in Adams; Ringer 1994). Surface erosion associated with burning is minimized by using burning under conditions that allow retention of the duff layer or by employing alternative site prep treat...

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...obability and abundance of fruiting in some understory shrub species. Thinning operations can also reduce shrub productivity if care is not taken to limit logging damage to the larger shrubs on site (=-=Muir et al 2002-=-; Wender et al 2004). Density management with the objectives of rapid diameter growth for overstory trees and regenerating an understory Snags equal or greater to the threshold diameter class regularl...

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...rd used to define old-growth (Oldgrowth Definition Task Group 1986). - constitutes a form “selection pressure” against the segment of the tree population that is genetically best adapted to the site (=-=Smith 1962-=-). See discussion on tree mortality at the end of this section. Untreated stands will produce the highest numbers of dead trees. Competition mortality in young stands is from the lower crown classes a...

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...multaneously, subsequent recruitment of additional cohorts may be limited because of dense hemlock canopies. Canopy openings suitable for establishing understory trees may not form for 300-400 years (=-=Stewart 1986-=-) unless there is active management to obtain the light level on the forest floor necessary for tree seedling survival and long-term growth. With few exceptions, converting a red alder stand to conife...

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...ast Range sites, where no buffers were left following logging, riparian vegetation regrowth along small streams (about 10 feet wide) will provide shade levels equivalent to mature stands in 10 years (=-=Summers 1982-=- cited in Skaugset 1992). Another study showed 50% of a Coast Range stream shaded within 5 years of harvesting and burning (Beschta et al. 1987). Our knowledge on the effect of shade on water temperat...

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...ndance of fruiting in some understory shrub species. Thinning operations can also reduce shrub productivity if care is not taken to limit logging damage to the larger shrubs on site (Muir et al 2002; =-=Wender et al 2004-=-). Density management with the objectives of rapid diameter growth for overstory trees and regenerating an understory Snags equal or greater to the threshold diameter class regularly recruited startin...

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...ose a sediment delivery risk. Density management treatments of this intensity will not prevent attainment of water quality protection with respect to sedimentation provided Best Management Practices (=-=USDI 1995-=- Appendix D) are followed. Density management with the objectives of rapid diameter growth for overstory trees and regenerating an understory Density management at this intensity will retain most of t...

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... reaching the forest floor (Oliver; Larson 1990). The light availability on the forest floor for the no thin treatment in a study of two 30-year old Coast Range stands was <2% to 6% of full sunlight (=-=Chan et al. 1996-=-a). No treatment in similar stands will not prevent attainment of interior microclimate conditions in adjacent late-successional stands. No treatment in similar stands will retard attainment of microc...

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...). However, conversion of sites inside the Riparian Reserve with a TPC classification of FGNW may increase the risk of sediment delivery by mass movement during the 3 to 10 years following treatment (=-=Gresswell et al. 1976-=-). This corresponds to the time needed for new tree roots to fully occupy the soil. Risks associated with the loss of root strength can be reduced by controlling competitive vegetation with techniques...

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... no buffers were left following logging, riparian vegetation regrowth along small streams (about 10 feet wide) will provide shade levels equivalent to mature stands in 10 years (Summers 1982 cited in =-=Skaugset 1992-=-). Another study showed 50% of a Coast Range stream shaded within 5 years of harvesting and burning (Beschta et al. 1987). Our knowledge on the effect of shade on water temperature is based on compari...

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... is minimized by using burning under conditions that allow retention of the duff layer or by employing alternative site prep treatments that do not involve exposing bare mineral soils on steep sites (=-=Brown 1972-=-a&b cited in Adams; Ringer 1994; USDI 1995 Appendix D). Soils on slopes that are less than the angle of repose are not at risk for landsliding. The angle of repose for most local soils is around 68%. ...

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... reaching the forest floor (Oliver; Larson 1990). The light availability on the forest floor for the no thin treatment in a study of two 30-year old Coast Range stands was <2% to 6% of full sunlight (=-=Chan et al. 1996-=-a). No treatment in similar stands will not prevent attainment of interior microclimate conditions in adjacent late-successional stands. No treatment in similar stands will retard attainment of microc...

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...met before the density management treatment. Canopy closure is <40% immediately following density management treatment. The canopy closure is projected to again be >40% about 5 years after treatment (=-=Tucker et al. 1993-=-). Alder/Brush field Conversions On landslide/ debris torrent prone sites, periodic severe disturbances will maintain red alders on the site. On sites where stand replacing disturbances are typically ...