questions about heart rot

[oldboy]

The other day I noticed the stump of a tree (pictured below) that went down just after a snow storm. Some of the wood near the heart of the tree appeared to be soaked and brown. I went in for a closer look, cut a cross section and poked around with a hatchet, the brown wood did not seem to be weaker than the other wood. The cross section reveled a brown area near the heart wood, is this heart rot? It had rained heavily in the area for a couple of weeks before the snow storm.

This tree is a Red Alder, and is very close to other Red Alders that I am climbing/removing. I am concerned about how I can tell if the trees I am climbing have rot too. I walked around the tree and took photos of some damage - I noticed a recessed area 5 feet below the break, and some superficial bark damage 5 or ten feet above the break.

Is heart rot not likely without obvious clues? What is the best way to assess for it before a climb? I didn't notice any fungi. Since the brown wood seemed solid, I doubt I would have noticed anything with a hammer tap test. If the weight of just half a foot of snow could bring it down, I bet I could too.

 

[beastmaster]

Heart rot is caused by fungus, and needs a way to enter the tree. The injury in this case is pretty obvious, but some times they can be pretty subtle or underground. The extent of damage has a lot to do with species. Some trees are better at containing it then others. Heart wood is made up of dead cells and is there to strengthen the tree, but lots of trees still retain strength so long as there is enough soild live wood surrounding the rot.
I will sometimes on removals if I suspect rot, drill the tree, and inspect the turnings. Conks and mushrooms are signs as are hollows and old wounds. I climb and remove trees with all kinds of rot all the time. Its white rot in the roots that scare me, though I climb them too most the time.
That skinny alder broke from a combination of rot, defect, cold and snow weight I'd bet. Unless the other near by trees have wounds, just being close doesn't mean they'll be full of rot too.
I'm no expert on this, and I'm sure there are some here who can give you a more detailed answer, but I hopes this helps a little.

 

[ATH]

Looks like there was a long vertical crack in the tree...right?

I think the brown you are seeing is the beginning of decay...but it is obviously not advanced through most of the crack (evidenced by your report of solid wood). The crack could have been caused by a host of different things (physical damage by another falling tree, another storm that partially bent the tree, lightning, fire, a buck rub, kid with a baseball bat, branching breaking and peeling, etc, etc.... Look up "frost crack". I am not saying that frost was the primary cause here...but there are several good publications about cracks like this under the overall topic of frost cracks (including articles that explain why that is often a poorly used term).

Looking at the pictures "stump" and "above stump" it seems like the tree's break started well above the original crack? Or maybe it was bent over by the weight on the top and broke from the bottom up??? You'll notice at the bottom where it broke there is an old branch wound (very evident on the right edge of "above stump". That was the weak point here. So, it broke off at the branch weak point and split to clean wood at the top...essentially I am guessing, the rot had little or nothing to do with this failure - but I'm open to suggestion to the contrary!

 

[oldboy]

Thanks guys,

Beatmaster, i'm gonna use that drill trick for sure, thanks!

ATH, I'm not sure where the break started. The tree was blocking the road, as I was cutting it up, the stump caught my eye. Your theory makes sense to me, Though there were quite a few neighboring trees that had the same lean and height that did not fall, also the area is heavily forested by them, and I did not see many other casualties. The "crack" or damage as I labeled it in the photo was at least 3 feet below and opposite of the lowest point of tearout on the stump. It sounds like you think the old branch wound (or knot) may have been the weak point/failure point, do you think a climber would be able to trigger that failure, or are snow covered branches able to apply much more leverage than a climber (climbing to a reasonable point)?

 

[ATH]

Hard to say looking at it...but I don't think that is something that would have broken with the weight of a climber. It is ALWAYS a good idea, though, to look at broken trees and ask these questions. Try to re-create the circumstances that led to the break. The more you do, the more you will understand what you should expect out of a tree.

 

[ch woodchuck]

We've worked red alder thru the yrs.Fast growing,like water and have a tendency to fall apart at an early age
If the canopy is green and appears healthy and the bark looks solid..thats a good sign.Broken branches with a thin canopy could be trouble.Doesn't necessarily mean the tree iis unstable..just something to be thought about.What we'd do is to use a rubber mallet.tapping the trunk all around the base and as high as possible.The sound of solid wood versus hollow/rot wood is quite distinct.Add BM's drilling suggestion,and you have a few tools which might make your life a bit easier...And a few less gray hairs!
Pretty good firewood..Good for smoking salmon too.

cheers

 

[BC WetCoast]

Red alder is an early pioneer species and is capable of fixating atmospheric nitrogen into the soil through nodules in the roots. When a forest site (in the PNW) is disturbed, alder is usually the first tree species to grow, adding nutrients to the soil, making the site more viable for species like Douglas fir later on. It is highly phototropic, meaning it will lean heavily, especially along the edge of openings, to get more light.

They rot very easily and are poor compartmentalizers. However, in this case I don't think the staining is caused by rot. I think that the wood has been stained by water entering through the crack and working down through checks and ring shake in the stem.

In my opinion, the original crack was caused by another tree/branch falling and rubbing the stem. From my experience, alder doesn't grow in areas where the temperatures get low enough where the trees frost crack.

Climbing alder can be challenging, often they have significant leans, smooth slippery mossy bark (they usually grow in wetter areas and places where it rains a lot) and the stems tend to be whippy without a lot of taper.

 

[climb4fun]

For specifically red alder, if you see places on the bark where it looks like rust has been leaking out, its a good indication of damage beneath the bark that you cannot see without removing the bark. I live and work in areas where alder is very common and have tons of them on my property.

 

[climb4fun]

"In my opinion, the original crack was caused by another tree/branch falling and rubbing the stem. From my experience, alder doesn't grow in areas where the temperatures get low enough where the trees frost crack."

We get Alders that freeze and split down here in Oregon near mt. Hood.