Cavities in trees

[Customcuts]

Lately I have been coming across quite a few trees with big cavities in them. My question is what is the best way to deal with these issues. The last one I came across was in a cottonwood that was in the crotch of a 30 ft limb that was coming off the central leader about 25ft above grind level. The cavity was about 80 percent hollowed out on a 16 inch diameter limb.:msp_confused:. It isn't above any objects like a house,fence,etc....the tree is already in a state of decline and I recommended removal. But what should I do to healthy trees with this issue??? Thanks in advance.

 

[Zale]

You might want to talk to Aerial Mason on this one. Are you trying to figure out the threshold where a cavity is considered a hazard?

 

[Customcuts]

You might want to talk to Aerial Mason on this one. Are you trying to figure out the threshold where a cavity is considered a hazard?

Yes, I know that it is only a matter of time before the cavity/limb fails, but I am also wondering what is the best method to maybe slow down the decay process and keep water out while allowing the tree to possibly heal over the cavity. I have been tip pruning to reduce weight and sometimes cabling on these cases just to minimize the potential for failures. Thanks

 

[arborjockey]

what's the client willing to pay? The problem I see would be the specie. Cottonwoods are known to have weak "wood" and core rot. Is there grass under the tree? Look up diseases, take soil samples, and ask the home owner t the history of the tree. Ask what the history of the soil is. Everything from grade changes to concrete work around it. Maybe some core samples. If the soils questionable amend it. Hard to say not being there. I hope this isn't a 30' overgrown shrub we're talking about:msp_sneaky: a second opinion from a veteran arborist would be a professional thing to do if your not sure. If $ is no object the tree can be saved.
:msp_smile:

 

[sgreanbeans]

But what should I do to healthy trees with this issue??? Thanks in advance.

Depends on how much good wood is still there, if it is below 10% then you should take it. If it does have more, leave it alone. If it is dry, clean it out. If it has water, leave the water in. Pathogens cant survive without oxygen, so if it has water............
Never fill the cavity's, those are all old wise tales, it will actually hurt the tree instead of helping it.

 

[Customcuts]

So don't go buy a bag of concrete to put in the holes? Lol.
The cottonwood I was referring too is about 70+ft. And about 35"-40"dbh. It's definitely a good sized tree... So get a second opinion from a more experienced arborist. I am not a arborist yet but I hope to be one day. So ill clean the cavity, leave water in the hole if water is present and check the soil and adjust it as needed. Alright thanks guys. I appreciate it.

 

[imagineero]

But what should I do to healthy trees with this issue???

I havent seen any healthy trees that were 80% hollow.

70% hollow is the threshold commonly cited in aus for structural instability and generally leads to removal.

Shaun

 

[arborjockey]

Where's the hole? Is it just hallow or does it have an opening. How bigs the openaing. 24" tree you only need 2" of "good wood" to be structuraly ok. In most cases if the tree is leaning make sure you have more good wood on the tension side. Hallow is one thing but if the riot gos through into the bark the scenario has changed. Now the the % is down to a 1\3. Lots of things go into the evaluation. I used to have all the grapghs and paperwork. Resistograghs, mallets for striking, coring bits etc....now I just use the coring bit. Problem is the specie they rot everywhere. Meaning most trees have a tendancy to rot at the base. I've had those things go bad 30' up. They'll be a big swell in the tree with water and stink pooo. Anyway just my experience. This is what I do with the 1\8"x14" driil bit. Put a foam ear plug on the tip. Then as I drill in(checking the tailings for discoloring) and when I hit soft wood I stop and pull out the drill. Now the foam tip has my measurement. 6 different places and im done.. Or if its a removal take your saw and do a bore cut in line with the trunk and check for rot. Good luck. Take pics.

 

[Customcuts]

I havent seen any healthy trees that were 80% hollow.

70% hollow is the threshold commonly cited in aus for structural instability and generally leads to removal.

Shaun

The tree that was 80 percent was a cottonwood which is in decline already. I was just refering to healthy trees with open cavities. Thanks for the tip.

 

[Customcuts]

Where's the hole? Is it just hallow or does it have an opening. How bigs the openaing. 24" tree you only need 2" of "good wood" to be structuraly ok. In most cases if the tree is leaning make sure you have more good wood on the tension side. Hallow is one thing but if the riot gos through into the bark the scenario has changed. Now the the % is down to a 1\3. Lots of things go into the evaluation. I used to have all the grapghs and paperwork. Resistograghs, mallets for striking, coring bits etc....now I just use the coring bit. Problem is the specie they rot everywhere. Meaning most trees have a tendancy to rot at the base. I've had those things go bad 30' up. They'll be a big swell in the tree with water and stink poo.

The hole was in the crotch and full of water on a cottonwood. The homeowner is saving up for the removal... Thanks for the advice guys. I will take pics and videos

 

[ROPECLIMBER]

Got me reading again here is one short read
Risk Assessment draft Tree World cavity
little longer read (wish these were dated)
http://www.isa-arbor.com/education/resources/educ_Portal_Risk_Whitepaper.pdf
Some Bartlet adds
http://www.illinoisarborist.org/Risk Management Update 10-2011 Handout.pdf
my 2010 study guide;for fruther reading chapter 12
ISA Itroduction To Arborcultuer: Risk Assesment & Tree Protection (CD-ROM).
Luley, 2005. Wood Decay Fungi.
Matheny and Clark, 1994. A Potographic Guide to the Evaluation of Hazard Trees in Urban Areas,(2nd ed).
Merullo and Valentine, 1992. Arborculture and the Law.
Schwarze, 2008. Diognosis and Prognosis of the Development of Decay in Urban Trees.
and since then they have a new ANSI standard and ISA BMP on Tree Risk Assement
ANSI A300 - Best Management Practices Tree Risk Assessment Combo
I need to read up more on this as the study guide is just a drop in the pond on the subject wish I had the time and $ to go to one of the Risk Assessment Cert Classes.
I hate Cotton woods,
Paul