What can I put in a tree to fill a small cavity?

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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?
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.
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.
Wood already has a lot of moisture; there is no benefit to keeping water away from moist wood.
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.

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.
 
Hmmm...if fungus can't grow in anaerobic conditions then maybe it would be best to keep the cavity full of water all the time. You know, hook the tree up to the sprinkler system, or something. That way at least you wouldn't be breaking any boundaries. ;)
 
Oxygen dissolves in water. That is how fungus can be cultured in a sterile liquid medium. Water is not anoxic, otherwise aquatic life would not survive in it.

I understand you're mildly joking since de-oxygenating the water before filling it and sealing the water in would be a tough trick:rolleyes: . Besides the cavity can never be fully submerged. It'll only pool water up to the edge of the cavity opening, but will still allow the wood inside and above the non-submerged part to moisten and swell. That's just an inherent property of wood we have to accept.

Also, the more water that is in there, the more downward hydrostatic pressure there is to possibly force water downward into the tree's trunk. it's a little thing called the law of gravity.
 
Originally posted by Tree Machine
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.

So if water is taken out of a cavity the decay will stop? You are saying there's not enough moisture in the tree to start with for wood decay fungus to grow?

Originally posted by Tree Machine

The callus will eventually close over the wound site and we have a successful CODIT scenario.


Once the cavity is closed over the decay stops? No water can get in. Seems simple then, just dry it out, close the hole over and the problem is sloved!

NOT!

Here's my theory why; it's like if you had athletes foot fungus and you dried your foot and put a plastic bag over the foot to keep out water, it wouldn't work because your foot has plenty of water in it, just like a tree has plenty of water in it for wood decay fungus to thrive.

The codit walls are chemical barriers to decay, that's what stops decay from advancing, not lack of water. Once the decay gets past the barrier, it has everything it needs to thrive.

In a successfull codit, the size of the cavity is determined by where the walls were set up, which is determined by the size of the injury or lost limb, not by how soon an arborist steps in and plunges his saw into the tree, or how quickly the opening is grown over.
 
So if water is taken out of a cavity the decay will stop? You are saying there's not enough moisture in the tree to start with for wood decay fungus to grow?
Mike, what I'm stating is pure, basic biology. If fungal mycelium is 90% water and it's growing in a pocket that's 20% moisture (hypothetical moisture #) then WATER will be the rate-limiting growth factor.
a tree has plenty of water in it for wood decay fungus to thrive.
In the tree, yes. In the cavity pocket, as you stated, water is re-routed around the wound site. Water is not fed into the cavity from inside, only from outside in the case of rain water being allowed to enter.

I can't comment on your human foot being compared to a tree theory. Biologically, they're incomparable.
 
TM, I don't think you've seen Mike's feet.;)

The subject isn't really cut and dried...and wet and dried and rewet and.......

Haven't most uf us seen cavities that wet and dry but haven't decayed? Haven't we cut trees thah had decay moving up from the base and no injury above that connected to the rot? Haven't we seen dry-rotted wood" Wood that had fungus(which did/does require some moisture) but which is never very wet?
 
my god...this is clearly a point of contention in our business. i went on vacation for almost two weeks and this post is still alive.
this post may live longer than the tree with the cavity in question.
what happened with the tree anyway? did it get filled or not?
 
Re: Am I right or wrong?

Originally posted by MasterBlaster
I tell customers that are worried about ground level cavities all they need to do is 3 or 4 times a year spray some pesticide
Butch, I'd have to say wrong. Most ants are actually doing good, keeping the cavities cleaner. Removing the rotten stuff is removing insects' habitat, and also is the best way to measure the hollow. This can be useful information if the owner is concerned about stability, not that every hollow tree is unsafe.

I'm just diggin' watching mm and tm go at it, I needed a break...
 
Allow me to divert for second or three...

How about what NOT to put in a cavity, eh?

Cement- bad. Rocks... worse.

36" dbh maple, remaining 15' piece. Shoulda been an easy drop and buck for an hours' work.

Ended up taking FIVE. 3 chains (not counting the re-sharpening), 1 axe, and alot of sweat later, finally got it into the truck.

So, don't ya just HATE it when some a$$hole fills it with something a chainsaw won't cut?
 
I'm just diggin' watching mm and tm go at it, I needed a break..
This really isn't about TM vs MM. He and I are having stimulating conversation amongst and with the rest of us. It's not a contest. There's a lot of love being exchanged here.

Personally, I'm not trying to get people to see things my way. I'm sharing my knowledge of fungal biology, the natural interaction of trees and fungus and how we (arborists) can possibly give a tree an advantage in outracing fungus on its quest toward a successful compartmentalization.
 
Originally posted by arboromega
my god...this is clearly a point of contention in our business. i went on vacation for almost two weeks and this post is still alive.
this post may live longer than the tree with the cavity in question.
what happened with the tree anyway? did it get filled or not?

yeah what has happened to the tree!i hope its been ''saved''after all this discussion.guy you should go help out with your cavity scraper:laugh: anyway both TM andMM are only wanting the best possible outcomes,knowledge on subject which is now subjects.guy ill post some pics of bad ants for you,trunk swells etc.
 
"Cement- bad. Rocks... worse"


I figured Erik would post after our much enjoyable afternoon. Off to the chain grinder this morning.:(
 
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