How to secure a cable
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I have a cedar that is at risk of falling over that I don't want to lose. I want to secure it on one side by putting a cable around it with some leather up against the tree to give it some support. I figured I'd attach the cable to either an oak that's about 15 yards in the direction the cable would need to go or just putting a few hundred pounds of cement in the ground and putting an anchor in it.
My question is, with a plan of pulling the cable taut with a 2 ton come-along, how do I then secure the cable? And what size cable should I use?
I guess it depends on how big the tree is and how much pressure needs to be applied.
A 1/8" steel wire rope as opposed to stainless will have a breaking strength of 2,000lbs. If you have a crimper, you use a sleeve and crimp the rope or you can use what most people will use is cable clamps, use two to form the loop. Then I would attach a turnbuckle to to it with another short length of rope attached one end to the turn buckle and the other to whatever you are going to anchor it with. If you anchor into concrete, you can use a bolt, 5/8" bolt will be more than enough, use a flat washer and nut on the end that will be embedded in the concrete. You will have to dig a fairly deep hole if you use concrete, you need weight and the ability of the undisturbed earth around the concrete to provide pressure to keep from pulling the concrete sideways through the earth. for what you are doing, I would dig at least a 12" diameter hole and dig down at least 3' preferably 4'. 3/16" wire rope has a breaking strength of 4,200lbs
Displacement is the key if you are using concrete. The size of the tree and its lean angle will determine the footprint and dimensions of the concrete footing. A few hundred pounds of concrete ain't gettin' it.
The Rock
You also have to take wind into account. The stronger the wind, the more force it exerts on the tree. You can get away with less displacement if you install a pier. If you go with less weight, you have to go deeper and pour the concrete up against undisturbed earth. The more pressure you anticipate being applied to the tree, the deeper the pier or more weight you need. Frankly without engineering you're only guessing. I would opt for anchoring to the Oak.
I doubt you will need concrete. Just pound in two or three metal fence posts such as you see all over ranches and farms into the ground. Pound them into the ground at a 30-45 degree angle then secure the cables at or near ground level.
When you wrap the cables around the tree, make sure to 'pad' the part of the tree where they are placed. Otherwise as the tree grows, the cables will dig into the tree damaging it and scarring it.
If you really want to save the tree, you should consult with your local horticulture extension office or a certified tree surgeon.
If you are really set on holding it forever......let me know and I can run some calcs on it with a little added info. Some of what was said above is correct, some less close to correct.
Engineering it is the only way really verify what you are putting in will work.
CAS
I'll let you guys figure out the physics of your preferred anchoring method......
.....but....
......I'll also suggest that you cable through the trunk of the tree rather than around it.
Placing padding between a cable and the tree is good advice for temporary cabling around a stem. As noted the tree wants to increase in diameter as it grows and even a padded cable is likely to eventually girdle the tree. If you are diligent about loosening the cable every year then it will not always be tight and supportive and really only be a "catch it when it falls" system. A loose cable would also allow abrasion and damage to the cambium layer over time essentially partially girdling the tree.
It may sound wrong at first but the proper way to attach the cable is by drilling through a structurally sound part of the stem and installing an eye bolt held by a nut. With this method you are still causing two wounds to the tree but they will heal over just like the stump of a pruned branch. In the process the tree will grow around the bolt further strengthening the connection. Much better than hurting the tree all the way around.
There are many resources to be found on line regarding this subject. Search for certified arborist and proper tree cable attachment.
Good luck with your tree!
Use a trailer house/power pole type screw in type anchor If you attach it to the ground.
I should have included this, but the tree is about 12 inches in diameter and 20-22 feet tall. The tree is in an area that has had significant soil erosion and after recent 70 mph winds, is now leaning a little.
If I did drill through the tree, how would I attach the cable to the bolt. Are there bolts that hollow? If I drilled through the trunk up about 10 feet so it wasn't an eyesore, it'd still be about 6 inches thick. Would I run the cable through the tree or would I want to get a bolt that went all the way through the tree?
Could I just run the cable through the hole and then through a big washer and then make a knot in the cable? I still have the issue of pulling the cable taut. If I drilled into the oak and did the same thing on the other side, how would I do this? I'd like to get the tree straight up again if I could, although I realize that might be impossible.
This is what is described above. Just need a long enough bolt to get thru tree and still have room. And as mentioned above use two cable clamps. I always braid the ends together when making a loop with cable, but prolly not needed in this case. And I think the earth auger/anchor would be ok. Two would work better. I would put the anchors 10-15ft. And would put them at least 15ft from base of tree. And run a cable from each anchor to the loop in the bolt. I would use 1/4inch cable.
When anchoring make sure the wind will not blow against the anchor causing slack and snap back. I would find an arborist in the area for help.
I don't know anything about how best to bolt through a tree that you don't want to kill but I can tell you generally how to attach cables, anchors etc. In general if you want to attach a cable, you could drill a hole through the tree and attach an eye bolt with a nut and washer on the back side and a washer under the eye . To the eye you can make a loop with the cable either through the eye or use a shackle so you can remove it without cutting it. Personally I would make a loop around the tree with the cable and use a rubber hose around the cable to protect the trunk. Intuitively I wouldn't feel comfortable drilling a hole in the tree, but I know nothing about trees. The other problem with drilling a hole in the tree is as I mentioned before, you really don't know what sizes of any of this, bolts, washers, cable, concrete designs are going to be sufficient. without engineering to determine the potential loads you are only guessing. One thing I can tell you is what people generally think they need at face value is no where near enough when the calculations are complete. To pull the cable taught, and keep it taught etc, you can do with a come along initially, then on the end of the cable that you will use to anchor to whatever you decide upon, you attach a turnbuckle you can make adjustments and take up slack with the turnbuckle. Making the tree straight again, may require multiple attachments with cables at different points on the trunk. A turn buckle on one end of the cable is the easiest way to tension and to keep the cable taught. All of these components can be attached with shackles so they can be removed and adjusted as needed over time. If you can expect 70 mph + winds on a hillside working on the tree you will need to anchor to substantial ballast. Pounding a couple of steel stakes in the ground isn't going to remotely do it. I have somewhere a photo of a scoreboard installed somewhere in Ohio on a pair of 12" structural tube steel posts that were bent over 90* 6" from the ground in straight line winds. Look up the specs on 12"x 12" HSS. The point is, wind load is no joke. The wind can apply huge pressures on relatively small areas that are exposed to it. Consequently, without knowing any of this, you really don't know how big of a hole you have to drill through your tree because you don't know what size bolt is going to be required, what diameter cable, what size ballast, anchor bolt/bolts. You are describing a relatively small tree but it's all still a guess. The best you're going to get is generalities. I would take the offer of CAS_Hunter and have some engineering done if he can run the calculations. At least then you know what you need, the rest is just assembly. Another thing I just thought of is you could drill a smaller hole in the tree , just big enough to put a cable through and use a steel dowl, (pin) to put through the loop of the cable on the back side of the tree. Pulling tension on the cable will keep pressure against the pin and won't allow it to pull out. This would allow a much smaller hole. If you don't understand the attachment methods of the cable I'm describing, let me know, I would be willing to make up a small example showing the components involved and take a photo for you.
Check with the electric company and see if you can get one of those screw in the ground anchors they use to hole electric poles. They are great and you can use an iron bar the screw it in the ground.
Take the tree down. The height and diameter with soil erosion and lean angle and 70 mph winds will not hold the tree in place without a two well placed designed anchor system. One point cable with noted soil erosion and lean angle coupled with 70 MPH winds, the tree will walk off at the base taking the roots with it and the tree could actually topple in the opposite direction of the lean or will snap at the cable wrap. The stability of the roots below the tree is most important The tree is done.
The Rock
Rocky x2, it will cost you more down the road or fall and kill someone. Replant and grow it right.
I really would have to see it. Installing a Galvanized bolt into a tree is a bad idea....Stainless or Iron is better. I doubt I would recommend a bolt at all...but instead a strap like a section of tire would be best.
There are 'Duck bill anchors' and cables designed specifically for this application......though most will be too light to hold a tree that big.
Solving the soil erosion problem is key as you probably know and the best systems for that are the Keystone or Allenblock wall systems with a geogrid
Without knowing anything about your soil, among other things, I'd say utilize your oak if it is a large healthy tree (thinking 3x + larger). The guy with the handle forester is the one I would trust as far as anchoring to the tree. Keep in mind that your tree is going to continue to grow, thus you might have a large problem on your hands if you can't ever get the area stabilized. Having said that, you will always have the option of taking it down, albeit that process will be much easier now.
The soil is DG. The oak is plenty thick to hold it.
logger buddy taught me how to do this on my winch cable, they used it for huge logs
