I have a very large red oak tree that lost a limb (15" diameter?) longer than 15 years ago. I've been told that it is probably rotten inside and should be taken down as it would be a threat to our home if it came down due to winds or?? Is there a way to determine if the tree trunk is bad? I thought about drilling a hole in towards the center of the tree and seeing if there is any softness as the bit penetrates the tree. The trunk diameter is probably 3-4 feet near its base. Any thoughts/suggestions? Thanks in advance
how to determine if a tree is hollow?
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Are you just curious, or planning on taking it down?
There are many methods, including thumping it with a axe, bore drilling, bore cutting with a chainsaw, etc. But you don't want to damage it, if planning on keeping it. Might be worth calling a tree service, or your city parks / forestry department, and getting a free or low cost evaluation by an experienced tree person.
Philbert
Are you just curious, or planning on taking it down?
There are many methods, including thumping it with a axe, bore drilling, bore cutting with a chainsaw, etc. But you don't want to damage it, if planning on keeping it. Might be worth calling a tree service, or your city parks / forestry department, and getting a free or low cost evaluation by an experienced tree person.
Philbert
Would rather not take it down as the cost is quite high. I thought that drilling the hole would give me an indication of the condition and if it's not too bad, I could plug the hole with a wooden plug or fill it with epoxy to seal it up, but don't know if that's a good or bad idea.
Can you tell me about your experience with bore drilling and what is the best way to do that? How large a hole? I was thinking about using a 1/2" to 3/4" speeder bit and withdrawing it every 1/2" or so of drilling depth to see the wood shavings being cut away as I drill into the center. Also, do you have an idea of how to decide if it is too rotted and needs to be taken down? Thanks, Dave
I would not bore drill it if I wanted to keep it; some of the methods I mentioned are for safety when felling. And there are many factors which determine a tree's health. I would call one of the local people, mentioned above, and get a professional opinion. They may have other options, besides removal, that will still reduce risk to your house.
Philbert
Philbert
chainsawman123
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I was told you can get the tree x rayed to see\ in side
An arborist can perform Resistograph testing that will show if there are areas of decay in the trunk. A step further would be tomography, which will show a 3D picture on a computer screen of the level of decay and how it transitions through the tree.
Most Red Oak of any significant age are hollow to one degree or another. It does not necessarily mean they need to be removed.
Find an arborist with a tree risk assessment qualification on the ASCA website to give your tree an evaluation.
Most Red Oak of any significant age are hollow to one degree or another. It does not necessarily mean they need to be removed.
Find an arborist with a tree risk assessment qualification on the ASCA website to give your tree an evaluation.
If you are getting a free opinion (unless it is from a city arborist, or the like) it is probably from somebody bidding to take it down. I can already tell you their answer!
Expect to pay for a Tree Risk Assessment. it is a professional service - much like you'd expect to pay a doctor to diagnose you, a vet to diagnose your dog, or an HVAC technician to diagnose your air conditioner. A cheap resistograph is about $3000 new - and they go up pretty quick from there. A sonic tomographer (closest you will get to an x-ray) starts closer to $20K.
But LONG before drilling, learn to sound the tree with a mallet. If it sounds good all around, I don't even get the resistograph out of the truck. When we get hollow sounding areas, I sometimes want to know how much solid wood there is...that is where I use the resistograph.
As for drilling....think much smaller. no more than 1/8" hole. 12" is plenty long. - if the rot is deeper than that there is very little strength loss. Drill slow. If you know what you are feeling and looking for you can feel the resistance on the drill bit change and see the color of the chips change. This is what a resistograph is doing - the machine measures resistance on the bit and records that. Don't fill the hole.
Expect to pay for a Tree Risk Assessment. it is a professional service - much like you'd expect to pay a doctor to diagnose you, a vet to diagnose your dog, or an HVAC technician to diagnose your air conditioner. A cheap resistograph is about $3000 new - and they go up pretty quick from there. A sonic tomographer (closest you will get to an x-ray) starts closer to $20K.
But LONG before drilling, learn to sound the tree with a mallet. If it sounds good all around, I don't even get the resistograph out of the truck. When we get hollow sounding areas, I sometimes want to know how much solid wood there is...that is where I use the resistograph.
As for drilling....think much smaller. no more than 1/8" hole. 12" is plenty long. - if the rot is deeper than that there is very little strength loss. Drill slow. If you know what you are feeling and looking for you can feel the resistance on the drill bit change and see the color of the chips change. This is what a resistograph is doing - the machine measures resistance on the bit and records that. Don't fill the hole.
Thank you. I will look at the website again, but my first look found no one in my area.
Thank you for your thoughts. The tree is i a wooded area near our home. Taking it down would mean one less tree among many, so it is just the cost of removing it that is a concern. However, I can have it removed for less than the cost of the resistograph if I could even find anyone around here to do one. I do have a long 1/8" bit, so I may try that. Why not plug the hole? Is that not an easy entrance fir bugs etc?
The tree's natural response to wounding is triggered by exposure to oxygen. You don't want to block that.
