People have come to say their goodbyes. Some live in the neighborhood. Others, like me, had to drive to make it to the tree’s memorial. We read about it in the newspaper and didn’t want to miss our chance. There’s a guest book people can sign. I stand in the yard with strangers, watching as people come and go, paying their respects, on this day that seems too sunny for grieving.

A few weeks ago, the owners of the house where the old oak stands got a letter from the city of Portland, Oregon, saying that the tree was dying, dangerous, and had to be removed. The homeowners know how much this tree means to people, so they put out fliers, inviting them to “gather to lay under its branches, sit by its trunk, draw its majestic form, and share stories of the memories it has provided.”

They don’t know how old the oak is, but I overhear an arborist estimate 350 years. The owners, whom I know nothing about save that they love a tree, hope to count the rings in the tree’s bark once it’s cut down and find out how long its life really was.

I’ve seen people make pilgrimages to see rare corpse flowers blooming or to watch century plants unfurl their Dr. Seuss-like flowers before dying. I’ve seen crowds gather to see swifts flow into a chimney, visit yellow fields full of blooming flowers, or don glasses to look at the sudden nothingness of an eclipse. But I’ve never seen people celebrate the end of a tree’s life. I wish that more plants had memorials. That we noticed the dense shrubs where birds like to nest before we cut them down. That we took a moment to acknowledge the loss of a vacant lot, filled with plants, before it became a housing development. Instead nature just goes missing.

How many animals have made this tree their home? Where will they go when the tree is brought down?

When I first heard about the tree’s memorial, it felt like something from a Portlandia sketch, a parody of hipster living. It seemed too earnest to be real. But standing here, I don’t think there’s a better use of a Sunday afternoon than honoring something so old. This oak stood here for hundreds of years before the home was built. When settlers founded Portland in 1851, this tree had already lived longer than I can ever hope to. I’d need to link arms with at least two other people for our arms to reach around the trunk of the oak, whose branches dwarf the single-story houses around it.

Large as it is, though, I can see that the tree is terminal: Massive oak bracket mushrooms, bigger than my head, erupt from the bark, the fruit of a parasitic fungus. The tree’s roots, an expert said after examining the tree a week or two before, were likely already 20-percent gone. This oak species, Quercus garryana, can live up to 500 years, but they aren’t used to the new heat waves that have become common in the Pacific Northwest. Drought stresses and weakens trees, making them more vulnerable to infection.

As the wind rustles the green leaves shading us, visitors come and go, some staying for just a few minutes. I hear people tell the homeowners, “I’m sorry for your loss,” and the mood is both joyful and somber, akin to a wake.

Everyone looks up. Everyone touches the bark, gently. One woman, my mother’s age maybe, lays on her back in the grass and gazes into the canopy for a long time. Squirrels run in the branches. Birds sing. How many animals have made this tree their home? Where will they go when the tree is brought down?

I wonder how long it will take for the neighborhood to seem normal again, a bright patch of sun illuminating a place that’s been shaded for hundreds of years. I wonder whether the owners will plant a new oak in its place, or perhaps another kind of tree better suited to the climate we’re moving toward. Regardless, I’m glad to have this moment to wonder what the future will be like before it’s arrived. A memorial, I realize, is a time to transition from a world in which a beloved was there into one where they are gone.

As I walk away, I see an oak branch in my path. The tree is so large that a few branches hang down, close enough for me to touch them. The tree still looks so alive, is still the host to so much life — even the fungus that’s killing it. I touch the dry green leaves that are still unfurling and say goodbye.