Bent hickory

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wysiwyg

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Last May a nearby tree uprooted and fell onto a 30 ft tall shagbark hickory. The top of the hickory was almost touching the ground. After I removed the offending tree the following day, the hickory only had a few broken branches but only stood up about 45 degrees. It has recovered a little more since then, and is currently in the condition shown in the photo below. Is there anything I can do improve its odds of returning to normal? I can reach the entire tree with a pole pruner.
 

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I bet if nothing is done that this hickory will grow new limbs where they should be and the old top will die off. In twenty years it will take Detective Dendro to ever tell that this happened.

This tree was bent by force and the force is gone so it ought to auto correct.

If this tree was growing this way due to shading from larger trees and those larger trees or tree is now gone, it would most likely auto correct.

A little pruning in a few years to keep the old bent top suppressed may be helpful.

Some treatments could easily be worse then doing nothing at all.

Retired Certified Arborist.
 
Thanks for the replies. I took a close up photo of the impact area, it appears there is more damage than I thought. The tree retained it's leaves above the wound all summer, so I took the wait and see route. Does this change anyone's opinion? I was thinking of topping it below the wound.
 

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Come along the top straight and secure it straight with a metal pole and secure it straight. Leave it on for a year or too. Save that hickory

As Del pointed out, trees tend to restore their natural growth habit. I wouldn't be willing to work so hard to straighten a tree as first suggested above. I'd prune the bent top using a process called "subordination". My goal would be to force the tree into a straight growth habit until the bent portion could be pruned off completely. Your closeup photo reveals a complete split in the trunk where it was bent. This type of injury might seal over, but it often becomes a source of decay or future failure. If carefully pruned for the next ten years, when that hickory becomes a 70' giant, the current leader won't even be a scar on the bark of a relatively straight trunk.

When subordinating, you cut back the tips and lateral branches where you don't wish the tree to expand its growth, and you make sure that any branches competing with a new leader are also pruned off.

That is a lot less work than any attempt to straighten, and combines the natural tendency of the tree to maintain a shape with a bit of human intervention to accelerate and improve the final outcome.
 
Thanks for the replies. I took a close up photo of the impact area, it appears there is more damage than I thought. The tree retained it's leaves above the wound all summer, so I took the wait and see route. Does this change anyone's opinion? I was thinking of topping it below the wound.
I saw that too looking at the photo...Less likely to stay straight. What is the diameter of the tree? Looks maybe 6"?

I know its a little initially unappetizing, but if you cut it off at ground level just before bud break this spring, it will almost certainly sprout (called coppicing). In about 2-3 years those sprouts will be as tall as that tree is now - that's because you have an established root system feeding a new tree. It may have multiple sprouts. After the first year, cut off all but the straightest (don't worry about biggest).
 
It is about 6" DBH. The straightening approach is going to be very challenging as there is a tree line just off screen to the right (east), but no straight trunks to tie off to. I looked into subordinating pruning, but there aren't any branches remaining above the wound which seem to make good candidates. If topping isn't suggested, I'm leaning towards coppicing. I'm on the border of oak-hickory forest remnants with protected oak-openings within a mile and have been working for the the last 10 years to rehab the property with those habitats in mind.
 
... I looked into subordinating pruning, but there aren't any branches remaining above the wound which seem to make good candidates. If topping isn't suggested, I'm leaning towards coppicing. I'm on the border of oak-hickory forest remnants with protected oak-openings within a mile and have been working for the the last 10 years to rehab the property with those habitats in mind.

The subordination process is a slow, ongoing, take-your-time approach. With a good pole pruner, it should also be quite easy.
  • It's winter. You needn't do anything right now.
  • When spring comes along, the tree will begin growing new shoots, leaves will come out.
    • Cut off the tips of the branches on the bent section. That means anything above the fractured, bent stem. Your purpose here is to let the branch keep giving nutrition/photosynthesis to the trunk without allowing it to grow bigger. This encourages other branches to grow while suppressing the damaged parts.
    • Do NOT trim any new growth attached to the tree below the damaged section.
    • Some new shoots will form right at the damaged bend, probably where some twigs were snapped off. LET THEM GROW. One of them will become your new leader for the tree.
    • Somewhere along the line, the lower branches will begin growing up through the damaged section. While this will be good, you should consider pruning off lower branches at the trunk attachment when they grow out faster than the top of the tree. Pruning off the lower branches is how we enforce a natural growth habit on forest trees growing out in the open.
  • Once your tree has grown what you think will be a good leader (someday), then all you need to do is prune away any branch that competes with it for sunlight. It will flourish. As the top continues to grow, then you need to keep pruning back any sections on the old damaged branch that continue to flourish.
Eventually, the tree will be towering over the damaged section. When there are more "healthy" parts of the tree than remaining attached to the damaged section, this is when you just cut off the damaged branch and let the tree do its own thing.

If you don't have the patience to put in about 15-30 minutes per year pruning the tree, just cut off the top of the tree right below the wood-split. Be sure to use an angled cut. The tree will sort itself out eventually without any further assistance.

Trees have been living in the woods without our assistance for far longer than mankind has been making saws. You really can't screw this up too much.
 
Incidentally, coppicing doesn't always work. The only time to consider that desperate plan is when your tree is already growing active shoots on the tree or you just want to reduce a big tree down to a little bitty, new-looking one.

I have an active coppicing project going at the headquarters of the local fire department. Their entire landscape is filled with green ash trees, all of which are in various stages of decline from ash borers. (Not EAB, by the way). For a number of years, I kept telling the management that the trees were destined to fail, that they should quit pruning all the dead branches and focus on growing new trees.

Along the way, several of the dying trees started growing suckers. Rather than do a total removal with stump grinding, I persuaded them to leave foot-tall stumps with the plethora of suckers still attached. Once the thicket of suckers had established what I considered the best candidate for a new tree, I rigorously pruned back all the competing suckers, and now we have attractive new ash trees growing like weeds from a stump that still protects the tender bark from the lawn mowing crews that tend to bang all the bark off with their string trimmers.

Their management has seen that they are getting new trees without being obliged to pay for the replacements, and this is in complete agreement with a city policy that prohibits tree removal without their urban arborist's approval. So... We get continuing business from what would otherwise be dead trees, all from a budget that doesn't allow for planting new ones.

As far as that goes, the landscape architect planted too many of the damn things, anyway. It would be appropriate to have half as many trees if they were mature, but spacing the trees appropriately for mature stature doesn't seem to be a concept supported by the landscape architects. They seem to prefer lots of monoculture trees planted in straight rows that will all die off in 30 years from some new invasive disease. Hideous later, but damned good looking for as long as anyone will remember the architect's name.
 
But Del! That's a flat horizontal cut.

Jimmy Fallon Shame GIF by The Tonight Show Starring Jimmy Fallon
 
Incidentally, coppicing doesn't always work. The only time to consider that desperate plan is when your tree is already growing active shoots on the tree or you just want to reduce a big tree down to a little bitty, new-looking one.
...
You are correct that it doesn't always work. However, the probability of young, otherwise vigorous, hickory sprouting is pretty high (I have the charts somewhere in a forestry text book that I'm too lazy/don't care enough to go dig up right now - probability listed by species and diameter). You are counting on that same vigor to cause a response if you are wanting to train a new branch as a leader. We're really doing the same thing except I'm starting at the ground, you are starting higher up on the trunk. My reasoning is that the new trunk will be stronger without the defect from a relatively large wound and wonky growing branch coming out of it.

Coppice regeneration is an expected/planned response when managing a hardwood timber harvest and planning for adequate regeneration. I cannot begin to tell you how many woodlands I walk through that have a boatload of multiple stemmed hickory trees - that's the result of coppicing.

If there are active shoots from the base of the tree, in almost all circumstances (Basswood is probably the most notable exception among native hardwood trees) those are an indicator of a very stressed tree. The top is dying and the roots are sending up desperate attempts to generate more photosynthates. Yes, those new shoots can be successful as well, but it would be wise to figure out what caused the decline and ask if that needs addressed (as you did with the borers).
 
Here's a quote from the Carya ovata (Shagbark hickory) section from Silvics of North America:
"Vegetative Reproduction- Shagbark hickory is a prolific sprouter. Nearly all of the cut or fire-killed hickories with stump diameters up to 20 to 24 cm (8 to 10 in) will produce sprouts. As stump diameters increase in size, stump sprouting declines, and proportion of root suckers increases (16). Young hickory sprouts are vigorous and can maintain a competitive position in the canopy of a newly regenerated stand. After 10 to 20 years the rate of sprout height growth declines and hickory will normally lose crown position to the faster growing oaks and associated species."
 
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