Hongos
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Fungus
Fungi that lives in the wood can badly weaken a tree. That is why it is important to be aware of them. There are different reasons why a tree can be attacked by fungi, eg. from bad pruning and big cuts, or any wound of the tree.
There are other fungi that however are essential to a tree's health, eg. those that live in the soil and co-operate with the roots of the tree, making it possible fot them to absorb nutrients otherwise not available to the tree, and at the same time greatly multiplying the absorbtion area of the roots.
This big branch of an almond was close to dead.
On this picture you can see its brown in the middle, than a light circle, brown again, second bright circle and then bark. The inner light circle was all very dry and brittle, which means its not functional for the tree.
You can see a big fruiting body (of the fungus) on the right further up from the cut.
The fungus can spread inside the tree for a long time, without beeing seen.
What you see on this picture is the frutingbody, which is the visible external sign. When the fungus has gone this far, it has probably grown a lot inside the tree.
This is the sexual phase of a fungus. They more commonly propagate in an asexual way (it just spreads, in several different ways). They are very advanced creatures.
This is the same tree.
Since this tree had this fungus right by the bottom, and had almost no living branches, and on top of that was leaning a lot, I suspected it was likely to fall (which is a safety concern), and so decided to take it down.
This is what the tree looked like inside.
It was hollow, which doesnt necessarily mean the tree is ill (a tree can have a very big hollow and still be alive and kicking)
The water (with dissolved minerals) that the roots absorb travels up the tree in the middle of the trunk, which is made of dead cells that form millions of capillary tubes.
The sugar that the leaves produce (by fotosynthesis) then travels down the tree and the roots in the outer layers of the trunk: these are still living cells.