Readers of this blog will know that my favorite tree is my forest pansy redbud, indeed the related posts you’ll find at the bottom of this missive will point to the other blog posts where I have mentioned it. I love this tree because it has spring interest, in the form of the standard pink redbud blossoms, but it also has a somewhat unique purple colored leaf that creates nice interest in the summer as well.
I wanted one of these probably for 2 years before finding and buying one, and then, back in early October, disaster struck! A wind storm heavily, heavily, damaged the tree. Splitting the trunk in two places.
In retrospect going out and looking at the damage, it was bound to happen, the tree had grown so well that some limbs obviously outweighed the strength of their junction with the trunk, it should have had some preventative pruning done, but I was busy being a new dad.
Some people, when a tree is damaged like that, would just cut it down. If they think it’ll never be perfectly shaped again, they don’t want it. I personally think a tree that survives damage will have more character and be more interesting, plus, I did say it was my favorite tree, so I decided to repair it.
When faced with this sort of damage you really have two options, you can try to mend the split, which is possible when it is a 50/50 split or close to and there is still substantial amounts in tact on both sides. Or, if one side is severely weaker, it may not be able to be saved and so you’ll have to trim it up and make it as clean as possible. I had to do both.
The picture above is of the upper trunk split, this one you’ll notice is really severe with no structural integrity left on the right side. Trees do all of their physiology in the thin green moist layer right beneath the bark (xylem, cambium, and phloem layers, sometimes just called cambium) so if there isn’t enough bark area left to sustain the split branch, it’ll die. If you’re a few hours or a day after the damage and the leaves are wilting, you’ll know there isn’t enough cambium left. You might be able to do some heavy pruning so that the remaining foliage is better matched to the remaining cambium, but chances are you just need to cut the limb off.
So, for the damage shown above, the leaves were already wilting and the structure was so obviously compromised, so I cut the limb off, as cleanly as I could.
The above picture is of the lower trunk split. This is the first branching point of the trunk, the first main scaffold branch split off. In this case though the prognosis was much better, the leaves had not wilted in the least (and I was easily 8-10 hours after the storm) there was still structure integrity to the branch (it was hanging parrallel to the ground, not drooping all the way) and the split was probably 40/60. So I decided to fix it.
The first thing I did was some severe pruning to reduce the weight load of the branch. This branch had grown significantly during the summer and really weighed too much, I probably took off 70% of it’s mass. Just so I could lift it back into place as much as anything else.
I temporarily tied the branch up with twine, temporarily for a few reasons, namely because if you tie a tree you choke it. People run into this all the time with birdhouses. They do not want to “hurt” the tree so they use rope, twine, or wire (the worst) to tie a bird house to a tree. Really, the better thing to do is just to nail it. A tree can survive a puncture wound no problem, but if the tree grows into a rope or wire it’ll impede the flow in the cambium layer and choke it.
After the tree was in place I got out my power drill and bored a hole through the tree at the site of the split. Then I went down into my basement and looked through my screw/nut/bolt/nail organizer. In a bin called “toilet parts” I found some large brass bolts, these were perfect. Brass doesn’t rust, and being an alloy of copper it may have some antifungal properties. I put a large bolt through the hole and secured it.
I then drilled another hole a few inches above the split and put a longer bolt through there. I made sure the hole was slightly smaller than the bolt so I really had to shove and pound it in (thus making sure there would be no gap) and then I used a wrench to tighten nuts on both.
My tree was now a cyborg, and the actions I took may seem severe, drilling two holes, but as I said, trees can survive puncture holes no problem. There was another flap of torn bark and I actually brought out my nail gun and put some brad nails into that, more wounds, but the tree doesn’t mind them.
Eventually the tree will grow over those metal rods, incorporating them into it’s structure, and being all the more stronger for it, with no adverse damage, because they go through the cambium layer, not around it.
So, weight removed, gash mechanically repaired, now I had to worry about insects and diseases. I had both a can of tree pruning sealer and a can of natural shellac wood sealer. I had just read an article saying shellac was better than the other stuff and so used it. Shellac is an all natural waxy resin made by insects and used in everything from wood products, to food, to pills. You probably eat a little bit every day, it is harmless, but it seals wood good. Insects and diseases love open wounds and so it was important to seal the tree with something.
That taken care of, the last thing I needed to worry about was water. Just like with concrete, water can get in a crack, freeze, and then widen and make the crack worse. Even with the shellac the force of water expanding as it freezes was a potential hazard. What I eventually did, though which is not shown in the picture, is just put a bead of silicone caulk around the top of the crack (but not the bottom) preventing any water from seeping in, but if any does, still allowing it to seep out. Silicone is a neutral and inert substance and the tree will probably grow around it fine, or, after healing has progressed, I can take it out. Another option would be to wrap the tree in some sort of plastic, but that can hold in moisture too close to the bark and promote rot, I think my caulk solution is best.
I’ll post an update next year to show how the tree is doing.
Should you repair every tree? No, you shouldn’t, if there is a safety issue where the tree overhangs a structure or is where people often sit, walk, or play, you should always err on the side of safety. If the tree limbs are too big for you to manage to put back into place, you may not have to cut the tree down, but you’ll need to remove the limb. But, if your tree is not yet too large to manage (mine was only about 10 feet tall) you can try to repair it. It doesn’t need to be a total loss.