12. Coarse Woody Debris –Soil Erosion, Soil Mixing and Churning

367.  We especially need to know more about the fallen tree – soil interface, probably the single most important habitat and potential niche for the survival of organisms in drastically altered systems (Maser and Trappe, 1984, pg49-par1).    

368.  Fallen trees that are oriented along the contours of a slope seem to be used more by vertebrates than are trees oriented across contours, especially on steep slopes. Large, stable trees lying along contours help reduce erosion by forming "a barrier to creeping and raveling soils (Maser and Trappe, 1984 pg 4-par1). 

369.  Woody duff, regardless of type or size, takes considerably longer to decompose than needle and leaf duff do.  Needles, leaves, and small twigs decompose faster than larger woody material and essential elements are thereby recycled faster in the forest floor. About 140 years are needed for essential elements to cycle in large, fallen trees and more than 400 years for such trees to become incorporated into the forest floor; they therefore interact with the plants and animals of the forest floor and soil over a long period of forest and stand successional history (Maser, Tarrant, Trappe and Franklin, 1988, pg37-par2).   

370.  The logs being removed would otherwise serve a key role as erosion control and animal activity (Page-Dumroese, Harvey, Jurgensen and Graham, 1991).

371.  Debris has many functions ranging from soil protection to wildlife and microbial habitat. The management of coarse woody debris is critical for maintaining functioning ecosystems (Graham, Harvey, Jurgensen, Jain, Tonn and Page-Dumroese, 1994).

372.  Coarse woody debris can be incorporated into the surface soil horizon as freezing and thawing cycles move CWD into the soil. Additionally, CWD can be covered as soil moves downhill. Depending on the forest type, large amounts  can be left in the form of decaying tree woody roots. All of these materials, in the advanced stages of decay, can be active parts of the soil system as soil wood (Carbon Based Cellulose).  Because CWD is an important component of a functioning ecosystem, a portion of this material must be maintained. As the demand for forest products and the ability to utilize more fiber increases, less material is being left after timber harvesting or after salvage operations. These operations, in combination with past practices of slash disposal and site preparation, have reduced organic material in the forest floor, making CWD management critical (Harvey and others 1987). Consequently, recommendations for maintaining CWD for different ecosystems and forest types are needed (Graham, Harvey, Jurgensen, Jain, Tonn and Page-Dumroese, 1994).  

373.  Symplastless wood is also the dominant store of organic matter in stream ecosystems (Harmon et al. 1986); as such, it is an important source of essential element and organic matter input. Symplastless wood traps leaf and duff within aquatic systems, which extends the length of time this material remains and provides essential elements through decomposition (Triska and Cromack 1979; Harmon et al. 1986). Symplastless wood provides physical structure to the ecosystem and fills such roles as sediment storage (Wilford 1984), protecting the forest floor from mineral soil erosion and mechanical disturbance during harvesting activities. It ameliorates the affects of cold air drainage on plants, helps stabilize slopes, and minimizes soil erosion (Maser et al. 1988). Symplastless wood provides elevated germination platforms with reduced  duff fall accumulation and relatively consistent moisture regimes (Harmon et al. 1986; Maser et al. 1988; Caza 1993; D.F. Fraser, pers. comm., 1995). In stream ecosystems it protects stream banks from erosion and maintains channel stability (Triska and Cromack 1979; Sedell et al. 1988). Features that influence the ability of CWD to fulfill these functions include size (length and diameter), whether roots are still attached, orientation, degree of burial, and proportion of the piece that remains submerged (Sedell et al. 1988)  (Voller and Harrison, 1998). 

374.  Conclusion: What purpose and need is there, that the function of soil protection and churning with respect to forest (system) health go unobserved has it is in the “Burn and Clearcut Project”.  Claims that system health will increase by this product – processes – function being removed, is absurd.  What it clearly shows, is there is a purpose and a need to correct past false promise based treatments, which are still being used as a foundation for treatments proposed and approved in the “Burn and Clearcut Project”.  Sound science, with respect to system health needs to be considered in order to protect this once fertile forest, i.e., including but not limited too – animals and plants as well as fungi diversity and their connections and functions
What need and purpose is there to remove materials that would have functioned for more than 200 years and when removed the system would have to recover and then take at least 100 – 200 years to replace the mass which than would take 200 or more years to function functions as CWD?  That would only be true is the system was growing back just the way it was before harvest.  Data shows that it not.

375.  Something to think about:  By removing trees in the “Burn and Clearcut Project” future uprooting and churning, will be severely reduced. 
376.  The uprooting of trees lifts and mixes soil of the once fertile forest, an important ecological process.  In some areas soil churning by the woody roots of wind thrown trees retards development in the soil of impervious layers of mineral deposits, known as iron pan.  Without these processes, standing pools of water would eventually produce swampy forest sites (Franklin, Shugart and Harmon, 1987, pg 551).

377.  When it comes to ecological stages of trees and their importance with respect to forest health, in scooping, the USFS replies we do not foster those ideas or concepts here.  Here being the timber sale project.  What parts and processes of the system do they foster?

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