Hollowed out silver maples

[Farmer Ferd]

Ive been felling a lot of silver maples lately and they all seem to be hollow at one place or another. Ive been cautiously climbing them and have had no problems but I fear failure of the trunk below may be possible. There is no way I can tell how hollow they are before climbing short of drilling a core sample, and I cant do that for an estimate nor do I have the time. another problem is some of them are hollow some-places and not others. Has anyone else run into this? I'm in NJ.

 

[Tom Dunlap]

That's not uncommon in any maple species.

You can learn more about what the tree looks like on the inside by studying the outside. Learn to look for bulges or odd shapes. Trunk folds can be a clue too.

There are many books available with good illustrations. Pay attention to hazard tree books.

Thumping trees with knuckles, handles of handsaws or dead-blow hammers can teach you a lot too.

 

[smokechase II]

hollow trees

You can't do a CT scan and figure out exactly how hollow it is.
So if there is no way to view the rot through either an opening or a drill hole/increment bore, you are a gambling man.

At some point, every gambler is a loser.

I could give you a formula used on softwoods to determine danger tree removal near roads etc. But if you're not going to bore to determine rot. It's probably going to be off by a fair bit anyway on maples.

Does the arborist world have specs on how much rot is too much; 1) to climb, 2) to leave standing and 3) to safely fall?

 

[Treeman14]

Hollow does not necessarily mean weakness.

 

[treeseer]

Hollow means some weakness; often not much. smoke, we have formulas and protocols to follow on judginbg this, but in the end it is a judgment call.

I don't agree that we gamble and will lose. We can be lucky and smart and stay out of trouble.

 

[coydog]

I think most mature silver maples are hollow to some extent or another. I tend to look more at individual branch/ crotch attachment points when climbing. I've never had or seen a silver maple fail beneath a climber, I have had a big leaf maple top tear out from a previous topping cut, but that was from the angle I was loading it, I was double crotched so I got away with some minor bruises. climb smart and double crotch if your going out on a questionable limb. silver maples can be a workout.

 

[clearance]

Hitting it with something, like the back of an axe, like Tom says is a good way to find out. I have climbed many trees, maples, red cedars, hemlocks, alders, etc. that had extensive interior rot, some basically like a pipe. If you chose to climb it, hammer it down, do not ever shock load it by hanging anything from it, would you log with a bent tower that had no guywires? Also, when you are taking off the top and blocks make sure your undercuts are clean, no humboldts, you don't want it to rock.

 

[Farmer Ferd]

Thank you all. some good info Ill make sure I use the hammer method to at least get an idea of what I'm dealing with and as always I will be careful.

 

[maxburton]

Think about a solid metal bar versus a hollow metal pipe. They're both pretty strong for their size. Wood's like that too. In my opinion, most lay people are more concerned about hollow trees than they should be.

By the way, the last time I went to a TCIA show, I saw a couple of people who had technology to scan trees for hollowness and decay. If I remember correctly, one used radar and another used electric resistance. I think. Anyway they produced pretty reliable results, and one of them scanned for roots, too. But they were quite expensive, many thousands of dollars.

 

[jmack]

Ive been felling a lot of silver maples lately and they all seem to be hollow at one place or another. Ive been cautiously climbing them and have had no problems but I fear failure of the trunk below may be possible. There is no way I can tell how hollow they are before climbing short of drilling a core sample, and I cant do that for an estimate nor do I have the time. another problem is some of them are hollow some-places and not others. Has anyone else run into this? I'm in NJ.

touch trees ... uh this is where the art thing comes in

 

[alanarbor]

I second the sounding with a deadblow mallet. It can also help you discover dead or decayed areas under the bark.

I would suggest this book to help you to reasonably asess the risks you expose youself to when working on trees.

http://secure.isa-arbor.com/store/Evaluating-Tree-Defects-Field-Guide--P175C4.aspx

 

[bottlefed89]

Funny you all bring this up. I just did a removal yesterday, had a big maple that basically went up about 15 feet, and then split, one of the leads failed in the ice storm we had, I think in 02, and squashed part of the house it was near. I quickly drew a little bmp to illistrate what I'm talking about here... I don't know if this cavity began years prior to the storm, and weakened the part that failed, or began as a result of decay from the failure, though it seemed to be a rather large cavity for the latter. Basically, the remaining lead was intact, growing well, and was completely solid. I am amazed at the weight the the hollowed out base of the tree was holding. I pulled up to the tree in my bucket, and it was about 12' taller then I was at full extention, so the tree was about 65'-70' overall. It was about 66" DBH, and 40"+ at the remaining lead. If I can attach this corredcctly, the red indicates the cavity. At the but the cavity left a hole over 40", it is amazing the weight the remaing wood was holding...