Given that, how exactly are you concluding that there were no tree rings 6,000 years ago? Please give a detailed reason for this conclusion.
First of all: I'm not a scientist, so I can't help you here.
Second of all: no single scientist can help everyone --- they're just not that educated.
I've been asked to explain in detail astronomy, botany, chemistry, definitions of words, electromagnetism, fossils, geology, hydrology, idols, Jesus, etc.
This of course, is because I make claims, then support them with Scripture.
BUT --- to answer your question the best I can --- the inclusion of tree rings on the trees that God specifically called into existence would support the
Omphalos Hypothesis, which I deny.
Tree rings, navels on Adam and Eve, skinned knees, memories of things past; all that stuff, in my opinion, didn't exist in Genesis 1.
If most research shows that the tree rings give an unbroken record back more than 11,000 years; I say "whoop-dee-do".
If that's a major problem for the global flood crowd, then let the global flood crowd handle it; and if they come up with an answer, good for them; and if they don't come up with an answer, good for them.
People need to stop asking me scientific questions, then getting all sore and pouty about it when I can't answer (I'm not talking about you, specifically).