How old is an oak tree if it is three feet around? It is the longer leaf kind in Tx.?

Answers:
It is very difficult to tell the age of a tree without cutting it down and counting the annual growth rings, one for each year, or using a special tool to bore a small hole through the tree to take a sample.
The growth rings vary in width according to the conditions each year, ie water availability, excessive heat, damage caused by animals or humans and disease.
As the width of these rings vary there is no hard and fast rule as to the circumference of the trunk and the age of the tree.

Other answers:
A species would be good here, but a 3' dia. red/white/burr oak would be about 200 years old.

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A species would be good here, but a 3' dia. red/white/burr oak would be about 200 years old.

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