JW would respond to this this way:
***
w01 7/1 p. 22 Trees That Stand the Test of Time ***Some claim that Methuselah, a bristlecone pine growing at an elevation of 10,000 feet [3,000 m] in the White Mountains of California, is 4,700 years old. The Guinness Book of Records 1997 cites this specimen as the oldest living tree on the planet. Edmund Schulman, who made a study of these ancient trees, explained: "The bristlecone pine . . . seems to survive because of adversity. All the older individuals [pine trees] in the White Mountains are found near 10,000 feet [3,000 m] in a dry, rocky wilderness." Schulman also discovered that the oldest specimens of other pines likewise grew in harsh conditions.
*** w73 2/1 p. 84 Will Your Days Be "Like the Days of a Tree"? ***Since the flood of Noah’s day was some 4,300 years ago, are we to believe that some trees now standing, like the bristlecone pine that is said to be 4,600 years old, survived that event intact?
The possibility cannot be entirely dismissed. However, in view of the enormity of the Flood and the destructive effect of water, it seems rather unlikely. (Compare Psalm 104:6-8.) This, too, adds to the doubtfulness of the accuracy of tree-ring dating methods.