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age of a tree
この杉の樹齢は推定千年を超える。
This cedar is estimated to be over a thousand years old.
切り株の年輪を数えて樹齢を推定した。
I estimated the tree's age by counting the growth rings on the stump.
世界最古として知られる樹齢五千年のマツが存在する。
There is a pine tree known as the world's oldest, with an age of five thousand years.