On Friday I took my father for a medical check-up, and whilst I was waiting, I took a walk in the nearby park. It is not a particularly big park, so it was in fact several walks back and forth. And during that time I have spotted this stump uprooted stump.
It looks like it happened very recently, possibly (probably?) during the first big windstorm that hit our region on Thursday. But this tree was not broken, it was uprooted, and that is not something that happens very easily to deep-rooting tree like linden (probably Tilia cordata, it is hard to be exact with a stump). But in this case, the wind was only the final straw that broke the camel’s back.
You may remember my late cherry tree and how I explained that I have felled it because it was infested with heartwood-eating fungus. And that is the case of this one too, only here the fungus is visibly far more spread. The white-ish color in the middle is the wood that has been infested by the fungus. No healthy hardwood that I remember from the top of my head has this color and texture. When split along the grain, white mycelium fibers would be more clearly visible, and under a microscope, one could probably also see that the wood is much more porous than is normal.
The wood is still hard, when dried and struck it would probably give a nice thunk! and might be possible to work it into something beautiful, but its strength was severely compromised. Which is visible on the root-side of the stump.
Several thick main roots have white-ish color to them and they are broken in a way that healthy wood just does not break.
Luckily this tree did not kill anyone, although there was a severely mangled park bench in the direction of its fall. But trees like this do occasionally kill people in urban areas. What can be done to prevent that?
Well, look at another picture from the same park.
That is not poo at the base of this tree, that is a fungus fruiting body. I am not a mycologist and the fruiting body is far too much decomposed for me to even guess the species, but almost certainly is not a mycorrhizal fungus, those do not grow this close to the trunk. To me as a former dendrologist, this is most probably a wood-eating fungus and only a mycologist can ascertain otherwise.
Oak trees are not very susceptible to heartwood rot, so this might be sapwood fungus. In that case, the tree will wither and die within a few years, still standing and relatively strong. If it is heartwood rot, the tree should be felled immediately before its structural integrity is so impaired that a sneeze fells it. If unsure, the safest course of action would be to fell the tree before it endangers a nearby parking lot and an entrance to the school.
I had a similar experience at our local building supply store. At the border of their fenced-off outdoor storage was growing a huge, beautiful red-leaved beech tree. But during sewage renovations, its roots were damaged and I predicted then, that the tree will not survive for very long. A few years later I have noticed fungal fruiting bodies at the base of the trunk and I have said to the store owner that the tree should be felled asap before it becomes a hazard. The law in CZ does not allow to fell such big trees willy-nilly, not even on private property, but the tree was felled within a year so his application went through and somebody had to look at the tree before approving it. And when I have seen the stump, I knew that my advice was correct – it was similar to that of the linden tree stump at the beginning of this article. It did not look like healthy beech wood at all.
And that is what should be done to prevent such trees from killing people. Every park should be assessed at least twice a year by either a mycologist or a dendrologist (at best both). Fungal fruiting bodies are often transitory and there is a finite window when the infestation is visible on the outside of an otherwise apparently healthy tree which is, in fact, a ticking time bomb. And just because the fruiting body is not on the trunk but on the ground still does not mean it is not dangerous.
Near the very probably sick oak tree was this stump
It is too oak stump, and you can see that it seems to be decomposing more on the outside. That is usual for oak trees, the heartwood normally lasts longer. But it is not a guarantee. As a side note, I would love to come by and lop off the burl on the right side, there is some seriously beautiful wood in there I am sure.
Speaking of beautiful wood, look at the burls on this oak tree.
Pity that park maintenance is usually not done by very savvy people and I know from first-hand experience that most of these trees when they reach the end of their lives end up as firewood, despite there often being really beautiful specimens. A friend of mine has witnessed a burl worth probably over a hundred € being tossed into a wood chipper. It made me nearly cry when I heard about it.
And look at this sycamore tree.
Under that bark is some top-notch curly maple unless I am mistaken. And I do not think I am.
We as a society do not pay nearly enough attention to park trees. Not when they live and not when they die. I think they deserve more, in life as well as after that, even if it never were an issue of human safety. Which they are.