Need advice on hollow Black Walnut

Huskyvarnya Saws

Huskyvarnya Saws

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I guess I should start off by saying that my tree felling experience is pretty limited, I have probably around 15 of what I would call decent size trees (20"+) under my belt. Most of those were straight with the exception of a couple of slight leaner's that I had to do some wedge work on. I got myself into a bit of a situation this evening attempting to remove this Black Walnut down by our shop. The tree is around 24-26 inches in diameter with a slight back lean towards the shop on one of the main limbs where the tree splits around 10 feet up. There is also another good size limb on the other side working against the lean in the direction I want it to go I was pretty confident that I would be able to drop the tree where I wanted it with the use of some wedges, but once I started to cut my notch I became concerned due to the ease that my saw was cutting into the tree. In hindsight I should have stopped there, but due to my lack of experience I carried on. Once my notch was cut, and I knocked the notch wood out with my axe, my worst fears were confirmed. The tree only has 2.5 to 3 inches thick of good wood all the way around. I took some pictures in hopes that it would help explain the situation a bit better, but I know they aren't the best for showing lean, tree size ect. Any advice on how I should proceed would be greatly appreciated.


Here are some pics. Once I realized it was hollow I didn't bother cleaning up the notch. The taller section after the split is the one leaning back towards the shop. My notch is in the direction of the main road (not the driveway right next to the tree), the shorter section after the split is going that way as well. I can take some more detailed pics tomorrow if that helps.


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leaner_75.jpg
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leane2_2_75.jpg

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Huskyvarnya Saws

Huskyvarnya Saws

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P.S. I had the idea of rigging a snatch block to another tree across the road and then to a come along out of the danger zone. Then applying slowly applying tension while I make the back cut while leaving a thicker hinge than usual to compensate for the lack of holding wood due to the tree being hollow. If that is a terrible idea, please let me know and I will discard it immediately. Thanks again.
 
EchoRomeoCharlie

EchoRomeoCharlie

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This is why I always whack trees with my axe before cutting into them. You can tell a dangerously hollow tree like that right away by the sound.

I would actually prefer to pull a hollow tree VS using wedges for the fact that you are spreading the load out over a larger area and not creating shock load which could blow the section of the tree above the wedge out causing it to sit all the way back, possibly popping the hinge and letting her go. Using a come along allows you to very slowly add force while there is no saw running and allow you to hear if problems are starting.

In this situation, I would get a line up in the tree. Get it hooked up to a pulling device and get some slight tension on it. Make the back cut, get several wedges in on the back side to hold it from sitting back at all. Set your hinge, get the hell away from it, and pull it over. I wouldn't personally go with a significant hinge. Assuming you have good purchase on the tree with the line, and wedges holding it, a slightly larger than normal hinge should work fine we don't want that stem splitting up as we pull. As you pull on it and assuming it's not making a bunch of noise, every once in a while push the wedges in so if something does go wrong, it hopefully won't go over backwards
 
Huskyvarnya Saws

Huskyvarnya Saws

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my guess
you are already committed
clean up that notch
yes more holding material
i would use wedges , i would not pull on it
I appreciate the advice. Do you think that there is enough wood there to hold the pressure of a wedge, or maybe one on each side? What is there seems solid, there just isn't much of it.
 
Huskyvarnya Saws

Huskyvarnya Saws

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This is why I always whack trees with my axe before cutting into them. You can tell a dangerously hollow tree like that right away by the sound.

I would actually prefer to pull a hollow tree VS using wedges for the fact that you are spreading the load out over a larger area and not creating shock load which could blow the section of the tree above the wedge out causing it to sit all the way back, possibly popping the hinge and letting her go. Using a come along allows you to very slowly add force while there is no saw running and allow you to hear if problems are starting.

In this situation, I would get a line up in the tree. Get it hooked up to a pulling device and get some slight tension on it. Make the back cut, get several wedges in on the back side to hold it from sitting back at all. Set your hinge, get the hell away from it, and pull it over. I wouldn't personally go with a significant hinge. Assuming you have good purchase on the tree with the line, and wedges holding it, a slightly larger than normal hinge should work fine we don't want that stem splitting up as we pull. As you pull on it and assuming it's not making a bunch of noise, every once in a while push the wedges in so if something does go wrong, it hopefully won't go over backwards
The advice is much appreciated. That is more along the lines of what I had in mind, with the addition of wedges for extra insurance. I figured that there would be a fine line between not enough and too much hinge, due to possible splitting like you mentioned. Do you think maybe around 15% on the hinge would be a decent number to shoot for?

I intended on knocking the bark off the back of the tree with my axe for a little more wedge depth, but forgot to do it. I may have noticed it had I done that. Lesson learned. I'll be sure to give future trees a good wack to see how they sound. I was really surprised that this tree was this hollow. It didn't seem sickly or anything like that. I guess looks can be deceiving.
 
EchoRomeoCharlie

EchoRomeoCharlie

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The advice is much appreciated. That is more along the lines of what I had in mind, with the addition of wedges for extra insurance. I figured that there would be a fine line between not enough and too much hinge, due to possible splitting like you mentioned. Do you think maybe around 15% on the hinge would be a decent number to shoot for?

I intended on knocking the bark off the back of the tree with my axe for a little more wedge depth, but forgot to do it. I may have noticed it had I done that. Lesson learned. I'll be sure to give future trees a good wack to see how they sound. I was really surprised that this tree was this hollow. It didn't seem sickly or anything like that. I guess looks can be deceiving.
I wouldn't be able to say 'yes, 15%'. This is going to be a feel or judgement call by the person on the saw. I would have to be there and really see and walk around the tree to get a solid feeling for how much hinge I want. Really depends.

All I can really say is thicker than normal because obviously you're dealing with far less fibers than on a healthy tree. Small amount of fibers + back lean AKA Tension on the hinge at first instead of compression) = bad juju. As you know, it needs to be thin enough to allow movement without significant forces on the already compromised trunk, but thick enough to hold the tension of the back lean without popping the hinge before you can pull the tree up onto the hinge. Remember, wood is extremely strong in compression, not nearly as strong in tension. So, you want a thicker hinge at first to hold the tension, but thinner once you get the hinge into compression by pulling the weight of the tree up onto the hinge. However, because the tree is in the state it is, you don't really want to be cutting with the trunk under stresses of the pull line. Catch 22 issue, so you want to set the hinge perfectly the first time. That's impossible for me to really get a feel for without seeing the tree in person.
 
old CB

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I don't understand the idea that wedges would be better than a rope. I've seen where wedges get you in trouble when you have inadequate holding wood.

Get a strong rope about 2/3 of the way up in that tree--be sure you have the tree firmly in hand and not just a limb that could pull free. If you go too high with the rope, there's also the risk of breaking off the top. Too low, and you don't have good leverage. Put significant tension on the rope--I use a come-along for pulling, and your snatch block is a good idea as that has you out of the fall line if you need to pull more.
 
jooky

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I don't understand the idea that wedges would be better than a rope.
my thought is you can put tremendous force up on the wood that is there with wedges
A rope would put strain throughout the entire tree and the weakest part will break first, who knows where that will be, even the area you tied to, then the tree swings back and breaks 180 of where you want it.
rope is better if you dont care where it goes, you are clear
but yes, wedges can be trouble if all the wood is bad.
its all bad really. do both. lol
 
Harmon

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Yah when you got a sketchy a$$ hollow tree you dont want tremendous force anywhere. The weakest part will be where you make a face and back cut. In this situation wedges will keep your bar from getting pinched.
 
Huskyvarnya Saws

Huskyvarnya Saws

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All of the advice is much appreciated fellas. I plan on trying to get it on the ground Monday or Tuesday. I'll summarize my game plan here to see what you guys think before I take action.

Would there be an issue with substituting the rope with some 12,000 pound cable? I don't have a lot of strong rope on hand but I do have plenty of cable.
 
Tigwelder83

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Rope, cable, chain, doesn't really matter provided it stays together & is strong enough. In felling the outside edge is where your control is so being hollow isn't a huge issue. Leave your hinge slightly thicker than normal, 2.5" maybe a little less. You need to get your pull line up 20 to 25'. Pull till you start seeing movement in the top. Cut in from the back, not thru your hinge and pull it over. Couple very important points. Use a long enough rope / cable, don't pull too hard too early and barberchair the tree, don't cut your hinge off. You may be able to use a wedge, and the wedge may collapse into the trunk. Most importantly, don't do it alone.
 

Den

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Johnnyblade gave me some advice awhile back regarding cutting hollow tree's. I had never even thought of this until he brought it up. He said in some cases it may be a good idea to "band" the trunk with ratchet straps to prevent slabbing and all that other nasty stuff.
I imagine 2 or 3 heavy duty ratchet straps placed strategically would help.

.
 
unclemoustache

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my guess
you are already committed
clean up that notch
yes more holding material
i would use wedges , i would not pull on it

Dang....

No, do not rely only on wedges!!

Get a rope on that thing and put some good steady pressure as you cut. When the back cut is far enough, pull harder.

your plan in your second post is good.
if possible, trim off the branches on the backside to help ease it foreward. With so little holding wood, that thing could go anywhere.
 
unclemoustache

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All of the advice is much appreciated fellas. I plan on trying to get it on the ground Monday or Tuesday. I'll summarize my game plan here to see what you guys think before I take action.

Would there be an issue with substituting the rope with some 12,000 pound cable? I don't have a lot of strong rope on hand but I do have plenty of cable.

cable is good.
 
lone wolf

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I don't understand the idea that wedges would be better than a rope. I've seen where wedges get you in trouble when you have inadequate holding wood.

Get a strong rope about 2/3 of the way up in that tree--be sure you have the tree firmly in hand and not just a limb that could pull free. If you go too high with the rope, there's also the risk of breaking off the top. Too low, and you don't have good leverage. Put significant tension on the rope--I use a come-along for pulling, and your snatch block is a good idea as that has you out of the fall line if you need to pull more.
I concur.
 
Huskyvarnya Saws

Huskyvarnya Saws

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Once again, all of the replies are greatly appreciated. I plan on finishing the job here in the next day or two. Here is my plan on action based on the information I have gathered here.

1. Get a cable high enough in the tree to get leverage, but not so high that I risk breaking off what I am anchored to.
2. Apply a fair amount of tension to prevent the tree from leaning back at all when I am doing my back cut. I understand not to get carried away here before the hinge is set.
3. Get some wedges in the back cut asap to help stabilize the tree, but don't drive them in to the point where I am putting more pressure on the hinge prior to the back cut being complete.
4. Finish the back cut to set the hinge while leaving it a bit thicker than usual, but not to the point where I risk busting up the trunk when I try to pull it over. I understand that this will be a judgement call.
5. Once the hinge is set pull it on over with the come along at a safe distance.

I'll take my time on the back cut and periodically check tension on the cable to make sure it is good and firm. I will also be sure to check the wedges and adjust accordingly as I go to make sure they are doing their job as well.
Like I had mentioned before. I plan on anchoring a snatch block to a tree across the road, then setting up my come along in a safe area just in case things don't go as planned.
I may also put a couple of ratchet straps on the trunk to help prevent it from busting up prematurely like @Den mentioned. The logic behind that idea makes sense to me.

If anyone sees any issue with this, or would like to add something. I am all ears.
I'll be sure to let you fellas know how it goes, and get some pics.
 
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