Hello Andriy; It is common practice to use a "ring boring tool" to extract a core of wood whose growth rings can be counted. There are recommended steps to take to protect the tree when the core is removed. Best regards, Jim Des Lauriers

Thank you, James, but I would clarify the question: Hou can I infer properly the age of an INTACT living tree? E.g. can I extrapolate number of rings in the branch on a main trunk?

Andriy; Of course you can core a branch and it will give you only the age of the branch. You must be reluctant to core the trunk of the tree. If you are reluctant, why is that?

I've never seen a paper that had a method of reliably aging a standing tree without counting rings. It's a puzzle! Jim Des Lauriers

I agree with James that coring the trunk of a tree, preferably at its base, is the best estimate of its age unless you can count the number of growth intervals from persistent growth rings produced from the base of the tree trunk.

Estimating age from morphometrics is a difficult task, and perhaps a dubious mission when it comes to understanding the demography of a tree taxon (see Harper JL 1977, Population Biology of Plants pp. 677).

The only morphometric inference of tree age I'm aware of is counting branch whorls for some conifer species (usually with young trees where the whorls are more distinct).

Otherwise you could try coring a few nearby trees of the same species (assume same site index, same growing conditions) to make a general guess, but since you said you find a very old tree and not a very old stand, there probably aren't comparable specimens very close by (and also growth slows after a certain point).

As James said, even under good conditions these won't be very reliable methods - I'm just brainstorming what you might try if you don't want to do any coring on this particular tree. Good luck!