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Martin, Electrical Engineer
Category: Home Improvement
Satisfied Customers: 4922
Experience:  Design, construct, fix and grow stuff around and in the home.
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For professional arborist: How do you know when it is time

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For professional arborist: How do you know when it is time to cut down co-dominant trees? I have had two consults by arborists and one says the co-dominant trees need to go as they are dangerous. Whereas the other arborist was not concerned, saying they looked healthy. I had not planned on having a third arborist come out and break the tie, so to speak. Also, when walking around our back woods, one arborist tended to focus mostly on the observed leafing out of the trees. The other seemed to look more around the root flair and bottom part of the trunk. Are trees with good leafing still healthy? Or could they also be a danger of falling in high winds? Hope you can advise.

Hi, I'm a moderator for this topic. I've been working hard to find a professional to assist you right away, but sometimes finding the right professional can take a little longer than expected.

I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you. Thank you!


Customer: replied 4 years ago.

Since I really need some advice (i.e. my question answered), I would appreciate if you would continue to search. Thank you.

Hello and welcome. As i am also a lumber producer and cut my fair share of tree each year i could help you on this. The best is if i could get an overview photo of the trees with something (or someone in the picture to get a sense of scale), the area where you live (to know if hurricane or ice storm could happen), to know if there is building around/under them and the species of the trees.

Also, any arborist ever worked on those tree (doing weight reduction or any type of steel wire tying between branches )?
Howdy. I'm a certified arborist and can help with this. I have years of experience with tree-related hazard identification and amelioration.

You posed a lot of questions, let me try to answer them all. Yes, trees that are producing lots of leaves are generally healthy. But also, health does not have a direct correspondence to the risk of failure. Tree failures usually happen due to structural weaknesses / defects. Sometimes perfectly healthy trees without defects can uproot entirely in windy weather if the soil has been saturated by heavy rains. There's lots of variables to consider when inspecting trees for risk. Here's a good article from my professional journal:

When specifically looking at co-dominant trunks, there are several variables to consider. Having a co-dominant stem isn't necessarily reason enough to label it as a hazard. The first thing to consider is: if the tree split apart, would one of the trunks have the potential to do damage to property or endanger life? Co-dominant trunk tend to fall out from each other in a direct line perpendicular to their attachment. If the tree was right next to house, but the joining structure was such that each trunk would fall along side (instead of toward) the house, then there is minimal risk. Also, different species of tree ten to hold onto co-dominant trunks better than others. Douglas-firs, for example, tend to hold together very well, whereas cedars and maples tend to separate more easily. Also, there can be contributing factors. If you have not only a co-dominant trunk, but also severe lean, or decay in the wood near the junction, the risk is much higher.

Now, if you ID trees that have risk in excess of your comfort level, you need to choose how to manage that risk. Removal is an option, of course. It completely eliminates all risk from that tree. Of course, you lose any benefits you may have from the tree, also. It may be a good shade tree that provides cooling in the summer, for example. There are other ways to manage risk in co-dominant trees. You can install a cabling system. This is a way of essentially tying the trunk together so they can't separate from each other. This should be done by a professional. You can also do pruning to help reduce the weight of the portions of the tree that are likely to fail. Reducing the height and branch mass of these parts reduces the potential energy and leverage the tree has.

So, identify the hazards you have, decide whether or not you want to keep the tree for other considerations, and act appropriately.
W. Sorgen, ISA Ceritified Arborist
Category: Home Improvement
Satisfied Customers: 173
Experience: Bachelor's degree in forestry, and owner of a residential/commercial tree service.
W. Sorgen and other Home Improvement Specialists are ready to help you
Even with Mr Sorgen getting in i just want to mention that i am still willing to give you my 3rd opinion following the 2 arborists that visited you. Unlike Mr Sorgen, i can't give you any information on your particular problem without a photo or a very detailed written description of the info i requested.

Another precision, Mr Sorgen seem to talk about "Co-dominant trunk" while i was initially thinking you were talking about at codominant trees.

"Codominant tree - a tree that extends its crown into the canopy and receives direct sunlight from above but limited sunlight from the sides. One or more sides of a codominant tree are crowded by the crowns of dominant trees."

If you could clear this question for US, please do.

Codominant trees is my specialty as i always select tree to fell based on their vigor and health instead of their market value. I can give you plenty of techniques to know if your tree is ready to go or if it have still a long time with you.
Customer: replied 4 years ago.

Martin - I am talking about co-dominant trees that have two trunks growing out from one central trunk. I used the term co-dominant trees because that is the terminology used by the consulting arborists.

I see. That is an error when they don't specify it as it is quite a different problem. The term for forked limbs like this is "codominant stems". When talking about codominant trees it refer mainly to the crown of the tree and it is one of those 4 categories:
dominant, codominant, intermediate and suppressed

Even if Mr Sorgen seem to have answered you favorably because you rated him, i still feel that you are no more advanced in your choice? Tell me if we can close the question or if you expected a more step by step method to decide what to do with your tree. If you decide to continue i will need the data i asked for because unlike the 2 arborist i was not able to do a field visit.
Customer: replied 4 years ago.

I think I can close this question at this time. Thank you, XXXXX XXXXX your offer of assistance. I would be happy to provide a rating, but do not see that as an option here....

Ok, just putting you a possibility for a rating right now.
Martin, Electrical Engineer
Category: Home Improvement
Satisfied Customers: 4922
Experience: Design, construct, fix and grow stuff around and in the home.
Martin and other Home Improvement Specialists are ready to help you

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