The oldest living being on Earth is thought to be a bristlecone pine tree in California’s White Mountains. This tree, “Methuselah,” is about 4,750 years old, which means it had been alive for more than 2,700 years when Christ was walking to Jerusalem.

Sequoias 3,000 years old and redwoods more than 2,200 also live in California. The oldest trees on the East Coast are bald cypresses in North Carolina that might be 1,500 years old, and white cedars in northwestern New York thought to be more than 1,000. Some pines in the Hudson Valley were vital saplings before Columbus sailed west; there are 400-year-old oaks near Boston, and hemlocks, cedars and white pines in Maine hundreds of years old at least, meaning they occupied the spots we see them now before the Declaration of Independence was written.

It’s impossible, of course, to know how a tree experiences time. Our human experience is affected by our awareness of death – we have a powerful sense that, one way or another, things are going to come to an end, mostly sooner than we’d like. The oldest human died at 122, and the oldest living person now is 116. Last year Fred Hale died at not quite 114. He was born in New Sharon in 1890. But these are unusual life spans for people. The average life expectancy in the U.S. is now about 78. It was probably around 45 in premodern times. These are just statistics.

Whether plants and animals know they’re going to die is not known. They don’t act like they do, but who can tell?

You have to wonder whether there’s any real difference between 78 and 4,750 years in the first place. The Earth itself is about 4.5 billion years old, which makes the bristlecone’s life span about equivalent to a housefly’s 20 days. I was going to say: about equivalent to a bacterium’s life span, but it turns out bacteria don’t really have life spans – they just keep dividing, and no one has ever seen one grow old and die. The same is true of clone-creating plants like the quaking aspen, which throw shoots up out of root systems that live on more or less indefinitely while just the trunks succumb.

Maybe a lifetime to a tree is less like a length of time and more like the motion of seasons. It might feel like awakening cold in early spring out of dimness, like a baby, then generating shoots and leaves with teenage abandon, and throwing out flowers in the rosiness of early adulthood. As long as thunderstorms don’t knock them down, in their seasonal maturity they diligently transform sunlight and water into energy and sap through July and August.

In September the air turns clear, like a frame of mind possible in human middle age, and the trees blaze, the acorns drop. In Maine the chill of advancing age can be gorgeous. Later a windstorm might strip the branches, and in November comes a moment of seamless stillness, like a reflection on the time before autumn. Then winter descends, the life force returns to its roots, and about Christmastime the sun signals it all will rise again.

To a thousand-year-old arborvitae cedar, time might feel like this, lifetime after lifetime rolling up and back like waves on a beach.

Dana Wilde can be reached at dwilde@bangordailynews.net.