10. Coarse Woody Debris – Insects and Other Bonogens / Endangered Species
316. Note : Also see (#6. Coarse Woody Debris – Fungi Diversity
– Mycorrhizae – Bacteria / Endangered Species”)
317. 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).
318. Something to consider. 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,
319. Insects connect. Bark Beetles are animals that connect the
inside world with the outside of a tree. E.g., The bark beetle (Scoltidae)
(an animal) chews through the bark and thus connects the outside world with
the inside of the tree. As the beetle enters and begins to use the
tree, it not only introduces fungal spores but also initiates the nutrient
cycle with its first deposit of bodily, so-called, waste (bodily products)
(Maser and Trappe, 1984, pg 20-par 3)
320. Insectivorous species such as woodpeckers, small mammals and bears
forage on insects dwelling in CWD (Maser et al. 1979; Maser and Trappe 1984;
Samuelsson et al. 1994) (Tables 7.3 Id 7.4) (Voller and Harrison, 1998).
321. Besides nitrogen, other essential elements such as Calcium, Magnesium
, Potassium, and Phosphorus and other essential elements play key roles in
soil, plant and tree health as well as the health of the other associated
living organisms (Page-Dumroese, Harvey, Jurgensen and Graham, 1991).
See: (3. Coarse woody debris – Nutrients and Essential Elements)
322. 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).
323. Because of all of the internal activity, the longer a fallen tree
rests on the forest floor, the greater the development of its internal surface
area. Most internal surface area results from biological activity the
cumulative affects of which not only increase through time but also act synergistically
– insect activity promotes decomposition through microbial activity that
encourages the establishment and rooting of plants (Maser and Trappe, 1984,
324. 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).
325. One salamander the clouded salamander frequents so called rotten
wood, particularly Douglas fir in late classes II through IV. These
salamanders are often found under the loose bark of large fallen trees in
spaces excavated by, wood eating insects. In fact, young clouded salamanders
show a striking affinity for bark (McKenzie and Storm 1970). It has
been found twenty feet up in standing trees (Maser and Trappe, 1984, pg34-par6).
326. Internal succession is also influenced by temperature, moisture,
and stage of decay. A class I fallen tree, for example, has many readily
available essential elements that support opportunistic colonizers. As decay
proceeds its moisture holding capacity increase but essential elements become
less available because either they have been used or the remain locked in
the more decay resistant compounds of the wood. Ultimately, the rapidly
growing opportunists are succeeded by organisms with more sophisticated enzyme
systems, and decay continues (Maser and Trappe, 1984, pg37-par2).
327. The manner, which a fallen tree comes to rest on the forest floor
greatly, influences subsequent diversity of both external and internal plant
and animal habitats. The decomposing fallen tree provides a changing
spectrum of habitats over many decades’ even centuries. It provides
diversity within a given successional stage and forms a physical-chemical
link through the many successional stages of a forest (Maser, Tarrant, Trappe
and Franklin, 1988, pg41-par4).
328. A fallen tree interacts with its environment through internal
surface areas. A newly fallen tree is not yet a habitat for plants or most
animals. But once organisms gain entrance to the interior they consume and
break down wood cells and fibers. Larger organisms – mites, collembolans,
spiders, millipedes, centipedes, amphibians, and small mammals must await
the creation of internal spaces before they can enter. The flow of
plant and animal populations, air, water and essential elements between a
fallen tree and its surroundings increases as decomposition continues (Maser,
Tarrant, Trappe and Franklin, 1988, pg42-par2).
329. Decaying, fallen trees contribute to long-term accumulation of
soil organic matter, partly because the carbon constituents of well-decayed
wood are 80-90 percent residual lignin and humus. Decaying wood in the soil
and establishment of conifer seedlings and mycorrhizal fungi on dry sites
are positively correlated. Fallen trees also create and maintain diversity
in forest communities. Soil properties of pits and mounds differ from those
of surrounding soil; such chemical and topographic diversity in turn affects
forest regeneration processes. All this, especially large fallen trees
that reside on the forest floor for long periods, adds to spatial, chemical,
and biotic diversity of forest soils, and to the processes that maintain
long-term forest productivity (Maser, Tarrant, Trappe and Franklin, 1988,
330. As the fallen tree progresses through decay Classes II and III
of decomposition slippage of the bark, and eventually of decayed sapwood,
removes that favorable environment and the organisms within it from the top
and sides of the tree; that material, however, does not disappear.
Most of it accumulates loosely alongside the log to provide a new habitat
favorable to many of the same organisms as before, plus larger animals, such
as slugs, snails, salamanders, and small mammals (Maser and Trappe, 1984,
pg 29-par 3).
331. Conclusion: What purpose and need is there, that the capacity
and ability, of CWD, to function as an habitat for insects, thus a food source
for insectivorous species of animals such as woodpeckers, small mammals and
bears go unobserved in the “Burn and Clearcut Project”?
332. What purpose and need is there, that the capacity and ability,
of CWD, to function as a changing spectrum of habitats over many decades
even centuries go unobserved in the “Burn and Clearcut Project”?.
333. 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).
334. 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)
335. What purpose and need is there, that the capacity and ability,
of CWD, to function as diversity within a given successional stage and form
a physical-chemical link through the many successional stages of a forest
go unobserved in the “Burn and Clearcut Project”?
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