Tree Machine
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Then tell us, Mike, why do cavities get bigger? What's the mechanism? Why does it happen? What ARE the 'other' factors?
Fungus is a highly resilient plant, adaptable to just about any condidion earth has to throw at it, except for excessive heat, anoxic conditions and dryness. All it needs is moisture (since it is around 90% moisture itself, and a substrate on which to grow, namely cellulose.
In a cavity, are we really dealing with wood anymore? If it has been decomposed (eaten, digested, bioconverted) then it is not really wood, but rather a breakdown product of wood. Fungus can't live on that anymore, because it already has, and will continue it's movement deeper into the tree for its food source, unless there's insufficient moisture to foster it's growth, or the chemical / physical barriers of the wood's reaction zones are successful in stopping it.
If a cavity has intact compartmentalization walls, and water is not allowed to get in, mycelial growth slows, and eventually stops. Once the food source in the immediate area is consumed and water is no longer available, guess what? The fungus either stops growing, or dies. Advantage, tree. The callus will eventually close over the wound site and we have a successful CODIT scenario.
If water is repeatedly allowed to enter the cavity, dorment mycelium can be revived, wood cells swell, gravity draws water downward, the non-submerged parts of the cavity re-moisten and instead of successful compartmentalization, we have cavity expansion. Bacteria doesn't do this, viruses don't do this and bugs....? Any guesses on what they're feeding on in that cavity? Fungus. Everything eats fungus. We do, carpenter ants do and so do beetles, pillbugs centipedes and anything else you might find in a tree cavity. Fungus is at the foundation of the food chain. Most of us think of fungus as mushrooms, but those are just the reproductive bodies coming from a mycelial network that has fed from, and incorporated itself in a moist cellulose structure, in our case, a tree.
Water is not the problem. Fungus is the problem. Water is necessary for the fungus to thrive. If water can not get into a cavity, the wood in there will dry below a point where the fungus will not thrive. Advantage, tree.You see a huge cavity and some water and blame the water. Isn't it possible that there are other factors at work? Do you suppose the water came AFTER the cavity? And if that cavity was first, how do you know the water was the problem.
This is a pretty bold statement, unless you are to say that the condition is hopeless and there's nothing that can be done. I tend to disagree with this, based on the biological needs of fungus. Fungus can, and does grow submerged. Ask any mycologist about liquid culture or biofermentation. Ever heard of yeast? For those who don't know whether this critter is an animal, vegetable or mineral, it is a FUNGUS, though not much of a problem for a tree, however it does quite well fully submerged.Wood already has a lot of moisture; there is no benefit to keeping water away from moist wood.
Fungus is a highly resilient plant, adaptable to just about any condidion earth has to throw at it, except for excessive heat, anoxic conditions and dryness. All it needs is moisture (since it is around 90% moisture itself, and a substrate on which to grow, namely cellulose.
In a cavity, are we really dealing with wood anymore? If it has been decomposed (eaten, digested, bioconverted) then it is not really wood, but rather a breakdown product of wood. Fungus can't live on that anymore, because it already has, and will continue it's movement deeper into the tree for its food source, unless there's insufficient moisture to foster it's growth, or the chemical / physical barriers of the wood's reaction zones are successful in stopping it.
If a cavity has intact compartmentalization walls, and water is not allowed to get in, mycelial growth slows, and eventually stops. Once the food source in the immediate area is consumed and water is no longer available, guess what? The fungus either stops growing, or dies. Advantage, tree. The callus will eventually close over the wound site and we have a successful CODIT scenario.
If water is repeatedly allowed to enter the cavity, dorment mycelium can be revived, wood cells swell, gravity draws water downward, the non-submerged parts of the cavity re-moisten and instead of successful compartmentalization, we have cavity expansion. Bacteria doesn't do this, viruses don't do this and bugs....? Any guesses on what they're feeding on in that cavity? Fungus. Everything eats fungus. We do, carpenter ants do and so do beetles, pillbugs centipedes and anything else you might find in a tree cavity. Fungus is at the foundation of the food chain. Most of us think of fungus as mushrooms, but those are just the reproductive bodies coming from a mycelial network that has fed from, and incorporated itself in a moist cellulose structure, in our case, a tree.