6. Coarse Woody Debris – Fungi Diversity – Mycorrhizae – Bacteria / Endangered Species

179.  Again, I mention many insects, fungi, bacteria, and other organisms are thought to be harmful, yet very few of them are (SHIGO, 1999).  The insects and microorganisms have a job to do on earth. Many are "clean up" experts such as a fungus that parasitizing another mushroom fruiting body of another fungus (SHIGO, 1999 - Page 105 ).  These organisms break down dead organisms to release or recycle elements essential for new life. Some organisms attack others that no longer have a defense system. A few attack living organisms that are healthy.  In spite of abiotic destructive forces and biotic agents such as insects, bacteria, and fungi, humans still rank as the major destructive agent for trees in forests and cities. Ignorance of tree biology is a major cause of this (SHIGO 1999).   Less than 1% of the insects and fungi are harmful to humans. Think about that when you use a product that kills everything (Shigo, 1999).  Bacteria are very small. They do big things (Shigo, 1999).

180.  One great problem started with the false premise that wood was dead – this is the foundation of the heart-rot concept.  I have learned the heart-rot concept was the foundation for labeling many fungi that were bonogens as pathogens. 

181.  People who think all fungi are bad should go without wine, cheese and bread for starters (Shigo, 1999).

182.  Some of the mycorrhizal fungi that inhibit both mineral soil and so called rotten wood develop much more strongly in the wood than in the soil, and some appear to be restricted to so called rotten wood (Maser and Trappe, 1984 pg 29-par 1).  Mycorrhizae increase plant vitality and therefore such materials that strengthen the latter also increase survival of a species.

183.  Many insects and animals eat fungi and disperse the spores and probably occur through all decay stages of a tree.  The fungal grazers are food for predators, so the animal-plant interactions are a prelude to animal-animal interactions (Maser and Trappe, 1984, pg 29-par 2).

184.  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).

185.  Coarse woody debris management recommendations were developed by using ectomycorrhizae as a bioindicator of healthy productive forest soils (Graham, Harvey, Jurgensen, Jain, Tonn and Page-Dumroese, 1994).  QUESTION – What mycorrhizal research, was used to show, that thinning these areas and removing / reducing, the present and future CWD, would bring about new healthy forest conditions and enhance mycorrhizae?

186.  In B.C. known decomposer macrofungi that are dependent on CWD  include 162 species of bracket or shelf fungi/ conks, 364 species of other macrofungi, and some commercially harvested mushrooms, such as oyster mushrooms (S. Berch, pers. comm., 1995) (Voller and Harrison, 1998).   

187. Fallen trees harbor a myriad of organisms, from bacteria and actinomycetes to higher fungi.  Of these, only some of the fungi might be noticed by the causal observer as mushrooms or bracket fungi.  These structures, however, are merely the fruiting bodies produced by mold colonies within the log.  Many fungi fruit within the fallen tree, so they are seen only when the tree is torn apart.  Even when a fallen tree is torn apart, only a fraction of the fungi present are noticed because the fruiting bodies of most appear only for a small portion of the year.  The smaller organisms, not visible to the unaided eye, are still important components of the system (Maser and Trappe, 1984, pg 16-par 5).    

188. Fungal diversity has usually been overlooked in considerations of the management of forest. The more obvious plants and animals attract the attention of the casual observer, but foresters and ecologists need to recognize that the health of the forest depends on organisms and processes below ground (Amaranthus, Trappe and Bednar, 1994). 

189. Forest floor diversity is partly maintained by windthrown trees that create a pit-and-mound topography as they are uprooted (Maser, Tarrant, Trappe and Franklin, 1988, pg45-fig2.7).   

190. Preservation of a threatened or endangered species involves preservation of its habitat and the diversity that habitat entails. When such becomes a goal of forest management, managers need information not only on owls or small mammals, but also on the mycorrhizal fungi that form the base of the food web.  Removal of ectomycorrhizal tree hosts removes the energy source of ectomycorrhizal fungi, which will not fruit without their host plants (Amaranthus, Trappe and Bednar, 1994).

191. Certainly our knowledge of biological processes and their interactions within forest is incomplete, and we know too little about the cumulative effect of a wide range of stresses on the ecosystem. But integrative research at the ecosystem level shows clearly that the many processes operating within forest inter-connect in important ways. Further, diversity of microscopic and macroscopic plant and animal species is a key factor in maintaining these processes (Maser, Tarrant, Trappe and Franklin, 1988, pg1-par2). 

192. 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 successional history (Maser, Tarrant, Trappe and Franklin, 1988, pg37-par2).  Which would mean, that over time the diverse amounts of gymnosperms and angiosperms as CWD would support fungi of different species.  Some are obligatory for CWD of different types of wood.  E.g., Ganoderma tsugae is obligatory for tsugae snag or nurse log.  Also this 400 years of contributing to fungi is a part of a system, made up of multi- parts and processes that make healthy forest.

193.  Decayed logs on the floor of a once fertile forest are a reservoir for nutrients and well as essential elements.  They also act as a storehouse  for moisture providing moisture for plants and animals during dry times such as summer, so called drought (Page-Dumroese, Harvey, Jurgensen and Graham, 1991).

194.  During decomposition, logs and other forms of coarse woody debris (CWD) reduce erosion, affect soil development, store nutrients and water, are a potentially large source of energy (nutrients) and essential elements, serve as a seed bed for plants, and form an important habitat for fungi and arthropods (Kropp, 1982).

195.  The flow of plant and animal populations, air, water, and essential elements between a fallen tree and its surroundings increases as decomposition continues (Maser and Trappe, 1984, pg 12-par1).

196. Symplastless trees are structural components of great importance for forest dynamics and forest biodiversity.  The decomposition of trees provides an important link in cycling of essential elements in ecosystems.  In addition, many species of plants, fungi and animals are dependent on symplastless trees for nutrients and essential elements, habitat or substrate and nesting (Kruys and  Jonsson,  1999).

197. 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.  Soil, nutrients and essential elements deposited along the up slope side of fallen trees reduce loss of nutrients and essential elements from the site. Such spots are excellent for the establishment and growth of vegetation, including tree seedlings.  Vegetation becomes established on and helps stabilize this "new soil", and as invertebrates and small vertebrates begin to burrow into the new soil, they not only nutritionally enrich it with their feces and urine but also constantly mix it by their burrowing activities (Maser and Trappe, 1984, pg 4-par1&2).

198. As a log decomposes, many organisms such as plant roots, mites, collembolans, amphibians, and small mammals, must await the creations of the inner space before they can enter.  The flow of plant and animal populations, air, water and essential elements between fallen tree and its surrounding increases as long as aging process continues (Maser and Trappe, 1984, pg 12-par1).

199. Plant-nutrient –essential element.  The succession of plants on fallen trees is mediated by changes in essential element availability and physical properties over time.  Three broad phases can be defined: initial, optimal, final. Early invaders prepare the tree for later colonization by altering its physical and chemical properties during the initial phase.  The  altered tree provides the best substrate for a wide array of organisms during the optimal phase. Ultimately, the depletion of essential elements and physical deterioration of the wood during the optimal phase diminish its value for many organisms, so fewer species inhabit the final phase (Maser and Trappe, 1984, pg 25-par 5). 

200.  Studies show conifer logs, well rotted can be quite acid.  Ectomycorrhizae form with just a few fungi compared to adjacent less acid humus and soil (Trappe, 1977).  Conifers include but not limited to, Eastern Hemlock and Eastern White Pine. 

201.  Some of the trees we know to be ectomycorrhizae are Chestnut, Beech, Birch, Hickory, Oak, Hemlock and White Pine. Ectomycorrhizae absorb moisture and essential elements, and translocate them to their host plants, making ectomycorrhizae essential for the development of such ecosystems (Harley and Smith 1983; Harvey and others 1979; Harvey and others 1987; Marks and Kozlowski 1973; Maser 1990). Therefore, we assume their presence and abundance to be a good indicator of a healthy, functioning forest soil. Ectomycorrhizae have a strong positive relationship with soil organic materials (Harvey and others 1981). Soil wood, humus, and the upper layers of mineral soil that are rich in organic matter are the primary substrates for the development of ectomycorrhizae. (Graham, Harvey, Jurgensen, Jain, Tonn and Page-Dumroese, 1994). 

202. CWD affects temperature as well as moisture, which can have a benefit for certain beneficial fungi (Amaranthus, Trappe and Bednar, 1994). 

203.  So called rotten wood served as mycorrhizal inoculum for containerized western hemlock seedlings. So-called rotten wood from a clear-cutting was less effective than that collected from a forest. (Kropp, 1982) NOTE – A clear cut where everything is removed is NOT a FOREST!

204.  NATIONAL WOOD FIBER NEEDS indicate substantial increases in demand for wood fiber - based products. This demand has resulted in increased efforts to remove all available fiber at harvesting sites. Intensive fiber removal or intense wildfire potentially reduces the parent materials (duff and wood residues) available for the production of organic reserves in forest soils. This reserve, primarily in the form of humus, decayed wood, and charcoal, has been shown critical to the support of both nonsymbiotic nitrogen fixing and ectomycorrhizal activities in forest soils of western Montana.  Harvest and fire-caused reductions of organic materials on and in northern forest soils have been linked to reforestation problems. This study was undertaken to provide a preliminary estimate of the impact of varying amounts and kinds of soil organic matter on ectomycorrhizal development in mature western Montana forests (Harvey, Jurgensen and Larsen,  1981).

205.  Both season and site affect the relation between the number of active ectomycorrhizae and soil organic matter in these ecosystems. In the dry season or on the drier site, the high soil organic matter content yielded larger numbers of active ectomycorrhizae than did the low organic matter conditions. Forest management decisions with potential to disturb soils and reduce woody residues, particularly in dry Northern Rocky Mountain habitat types, should take into consideration the importance of soil organic reserves and their affects on ectomycorrhizae as a factor in forest soil quality. A consistent effort should be made to retain a moderate quantity of large woody materials. Preliminary estimates indicate that approximately 25-37 tons/hectare (Harvey, Jurgensen and Larsen,  1981).

206.  Abiotic forces as well as biotic agents play key roles in system health.
Fire, fungi and invertebrates are all heavily involved in the creation and decomposition . Wind and fungi commonly function together to create CWD (Edmonds and Marra,  1999). 

207.  As fallen trees progresses from decay class I to class II, the scavengers are replaced by competitors with the enzyme systems needed to decompose the more complex compounds in wood. The fungi involved in this activity are often mutually antagonistic, so that a given part of the tree may be occupied by only one fungus that excludes others by physical or chemical means (Maser and Trappe, 1984, pg27-par4).   (We call this altered area a niche)

208.  Various mites, insects, slugs, and snails feed on higher plants that become established on so called rotten wood.  These plants also provide cover for animals, as do the lichens, mosses, and liverworts that colonize fallen trees in decay class IV.  Wood-boring beetles, termites, and carpenter ants produce channels in heartwood (heartwood forming trees) that provide passageways for roots.  The fruiting bodies of the mycorrhizal fungi, produced from energy supplied by the host plant, can also be a major source of food for insects, arthropods, and small mammals such as the California red-backed vole (Maser and Trappe, 1984, pg 29-par 4). 

209.  Fallen trees harbor a myriad of organisms, from bacteria and actinomycetes to higher fungi.  Of these, only some of the fungi might be noticed by the causal observer as mushrooms or bracket fungi.  These structures, however, are merely the fruiting bodies produced by mold colonies within the log.  Many fungi fruit within the fallen tree, so they are seen only when the tree is torn apart.  Even when a fallen tree is torn apart, only a fraction of the fungi present are noticed because the fruiting bodies of most appear only for a small portion of the year.  The smaller organisms, not visible to the unaided eye, are still important components of the system (Maser and Trappe, 1984, pg16-par 5).   

210.  Decayed heartwood (of heartwood forming trees) splits into chunks;  roots grow down the resulting cracks as well as along insect channels.  Invertebrates – from minute mites to centipedes, millipedes, slugs, and snails – find shelter in these openings and passage along them.  Vertebrates such as salamanders, shrews, shrew moles, and voles, find cover under debris of sloughed bark and so called rotten wood alongside the class IV tree; they also find the so called rotten wood on the underside of the tree crumbly enough for digging tunnels or burrows. Fungi and other microorganisms abound on the wood itself as well as on the new substrates offered by the feces of animals (Maser and Trappe, 1984, pg 17-par 4). 

211. Ground contact by fallen trees creates opportunities for various interactions with the biotic components of soil and duff. Fungi, for instance, translocate essential elements within the soil- system, as both decomposers and root symbionts. Fungi also immobilize translocated essential elements and thereby enrich the decomposing wood substrates they inhabit. In addition, the colonization of decomposing fallen trees by nitrogen-fixing bacteria permits additional nitrogen accretion within the decaying wood (Maser and Trappe, 1984, pg 19-par 3).   (See my term organisms)    

212.  Colonization of decomposing wood by animals helps microbes to enter interior surfaces of the wood and creates additional openings for entry of water and essential elements; and penetration of the wood by roots of trees, such as western hemlock, facilitates entry by mycorrhizal fungi (Maser and Trappe, 1984, pg19-par4).

213.  Fungi feeders, E.g., In the Northwest - California red-backed voles to black tailed deer, may obtain some of their protein nitrogen from decaying trees by feeding on fungal fruiting bodies, such as what some call truffles and mushrooms (Maser and Trappe, 1984, pg 36-par3).        

214.  Logs may contribute significantly to reestablishment of animal populations by providing pathways along which small mammals can venture into clearcuts and other bare areas. This has relevance to the reestablishment of tree seedlings on bared areas since survival and growth of new trees depend on development of appropriate mycorrhizal associations. Surprisingly, fungal symbionts apparently disappear from cutover areas shortly after their host trees are removed (Harvey et al. 1978a), and the sites must be reinoculated with their spores. Many mycosymbionts have underground fruiting bodies and completely depend on animals for dissemination of spores. Small mammals are the vectors. They consume the fungus and carry spores to new areas, thereby inoculating tree seedlings (Maser et al. 1978a, 1978b; Trappe and Maser 1978) (Franklin, Cromack, Kermit, et al. others,  1981). 

215.  So called rotten wood is also critical as substrate for ectomycorrhizal formation. In one forest which contained a coniferous stand of trees, over 95 percent of all active mycorrhizae were in organic matter of which 21 percent were in decayed wood.  In another study in the northern Rocky Mountains, decayed wood in soil was important.  In moist, mesic, and arid habitat types (Harvey et al. 1979); it was the most frequent substrate for active ectomycorrhizae on the dry site, probably because of high moisture levels in the wood. Mycorrhizal fungi can colonize logs. presumably using them as sources of water, essential elements and nutrients.  (Franklin, Cromack, Kermit, et al. others, 1981). 

216. The mycorrhizal relationships may be important factors in establishment of seedlings on nurse logs; they are also important to mature trees. Just as quality and special properties of wood products vary by tree species. The natural ecological characteristics of logs also vary by species (Franklin, Cromack, Kermit, et al. others, 1981).  

217.  Sound CWD provides secure travel corridors for small mammals (Maser et al. 1979; Maser and Trappe 1984; Carter 1993), and provides subnivean habitat during winter. The value of this habitat is positively correlated with piece size (Maser and Trappe 1984; Hayes and Cross 1987; Carter 1993). Nordyke and Buskirk (1991) found that southern red-backed vole abundance was positively correlated with the decay stage of logs in the central Rocky Mountains. Maser and Trappe ,1984) and Rhoades (1986) reported associations of small mammals with CWD because of the food source provided by the fungal fruiting bodies growing in and on the CWD (Voller and Harrison, 1998).      

218.  Coarse woody debris functions as seed beds or nurse logs for some trees species and many species of bryophytes, fungi, and lichens, and some flowering plants (Table 7.6) (Samuelsson et al. 1994; D.F. Fraser, pers. comm., 1995; E.C. Lea, pers. comm., 1995) (Voller and Harrison, 1998).  

219.  We know other species are either associated with CWD or perhaps with the fungi that use CWD as their parasitic intermediate, such as the gnome plant (Hypopitis congestum), candystick (Allotropa virgata), and other ericaceous species. Ryan and Fraser (1993) reported that cryptogam species richness in coastal Douglas-fir forests was strongly influenced by available substrate. In forested sites, the presence  and rock substrates resulted in substantial increases in species richness. The review of Samuelsson et al. (1994) states that distinct Succession of bryophyte and lichen communities occurs as trees die, fall, and decay.  In B.C., known decomposer macrofungi that are dependent on CWD  include 162 species of bracket or shelf fungi/ conks, 364 species of other macrofungi, and some commercially harvested mushrooms, such as oyster mushrooms (S. Berch, pers. comm., 1995). These communities play roles in the germination and growth of other epiphytic and quasi-epiphytic communities. Climatic factors influence epiphytic communities, with lichens dominating drier ecosystems and bryophytes replacing them as conditions become wetter. The longevity of individual pieces  is critical to the persistence of many species with poor dispersal abilities. Dispersal in many species is from one log to the next, so logs close to each other are required. Samuelsson et al. (1994) note that large logs play a more important role than small logs in the ecology of bryophytes and lichens. Large logs last longer, have greater surface area, and have higher, steeper sides that prevent ground-dwelling species from invading. They may also be important in providing a relatively duff-free substrate for the establishment of some species of cryptogams (D.F. Fraser, pers. comm., 1995) (Voller and Harrison, 1998).            

220.  Symplastless wood facilitates a slow release of essential elements, ameliorates leaching, and provides a growing substrate for bryophytes. These buffer water and essential element release from duff and aboveground processes, especially processes such as nitrogen fixation in aboveground plants such as hepatics (Harmon et al. 1986; FEMAT 1993; Samuelsson et al. 1994) (Voller and Harrison, 1998).     

221.  Bacteria are very small. They do big things (SHIGO, 1999)

222.  Free-living bacteria in woody residues and soil wood fix 30-60% of the nitrogen in the forest soil. In addition, 20% of soil nitrogen is stored in these components (Harvey et al. 1987). Harmon et al. (1986) reported that CWD accounted for as much as 45% of aboveground stores of organic matter.  Symplastless wood in terrestrial ecosystems is a primary location for fungal colonization and often acts as refugia for mycorrhizal fungi during ecosystem disturbance (Triska and Cromack 1979; Harmon et al. 1986; Caza 1993) (Voller and Harrison, 1998).      

223.  Colonization of symplastless wood by fungi and microbes may be one of the most important stages in essential element cycling (Caza 1993); however, these processes are still relatively poorly understood. Soil wood contains a disproportionate amount of the coniferous non-woody roots or ectomycorrhizae in forests (Harvey et al. 1987). As one of the dominant sources of organic matter, symplastless wood is an important determinant in soil formation and composition (Caza 1993) (Voller and Harrison, 1998)   

224.  Few studies have examined processes, other than nitrogen fixation, that are responsible for net changes in essential element content of coarse woody debris. It is tempting to assume that the processes are the same as in fine duff, but recent research being conducted at Andrews indicates some differences. For example, during the early stages of log decomposition, fungal sporocarps transfer nutrients to the forest floor. Thus, in fine duff, fungi immobilize nitrogen, but in coarse woody debris they actively transfer it to the soil. Another important consideration in understanding nutrient release from coarse woody debris is that tree boles are composed of several distinct substrates. While wood may be slowly releasing nutrients, other parts such as the inner bark (phloem) decompose and release nutrients at rates similar to those of leaf duff. Hence an overall pattern of release from symplastless  trees may be a rapid loss of 10-20% of the nutrients followed by an extended slower release of nutrients. Finally, the role of fragmentation in transferring nutrients to fine duff in the later stages of woody debris decomposition is not revealed by patterns of net accumulation. The omission of transfers via fragmentation from previous calculations suggests (Harmon and Hua, 1991).  (NOTE:  it may be specifically unclear whether the paper is referring to  of essential elements or a true nutrient.  Both exist, and are essential for system health.)

225.  Checklist of plants and animals – There are few checklists of either plants or animals that inhabit fallen Douglas fir in Pacific Northwest.  [Let alone in other areas with other species in the USA – (Termed as profiles or unique features)].   No checklist of the microorganisms in fallen trees of western old-growth forest is available [I know of none in the east.]; the subject has hardly been studied.  (Higher fungi have been cataloged for many kinds of so-called rotten wood in Europe.)  Lawton listed the mosses that occur on so called rotten wood or stumps in the Pacific Northwest.  Deyrup (1975, 1976) has done a thorough job with insects and has identified about 300 species associated with fallen Douglas fir.  The only published checklist for vertebrates that use fallen trees is for northeastern Oregon (Maser and others 1979 not listed in references here).   (Maser and Trappe, 1984, page 18-par 2)  

226.  Conclusion:  What purpose and need is there, that the capacity and ability, of CWD, to be a major habitat, substrate and in some cases niche for fungi and play a key role in fungi diversity go unobserved in this “Burn and Clearcut Project”?  What purpose and need is there, that the capacity and ability, of CWD, to play key roles with respect to beneficial bacteria go unobserved in this “Burn and Clearcut Project”?


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