Last week I had to trim the vine again and as I'm doing this for years, I know every inch of it. There's one piece that always makes me stop and look at it for 5 minutes.
This is a part of the vine, cut years ago, you can see how dry it is and cracked. I don't know how old this vine it is, but must be at least 40 years old, if not older.
They say trees grow one ring each year and if you look at the cut offs, you can count the tings most of the times. I don't know if that is true for vine as well, but logic says it must be.
If you look at this one, you can count the rings, even though these are slim rings. But then again, I can be wrong and what I see are not rings, just the texture of the wood.
The beauty of the vine is that the roots are able to grow very deep in the ground, in order to find water. This is why you vine in the mountainside. It is often used for strengthening the mountainside and stop landslide. It doesn't need much soil as it's able to survive almost everywhere.