While I was in Arizona, something was bothering me. I wasn’t sure what it was. The land didn’t look right. I realized: no trees. Not that the entire state is tree-free, just that a lot of it tends toward shrubs and cactus. Near water, there are trees, sometimes even tall ones, but mostly the trees are gaunt and wizened, determined rather than flourishing.

I missed them.

The sky, however, is bigger there. Mountains ring the horizon. There is plenty of space. I begin to understand the people who collect bones—they are used to what is structural and essential. What is green, what is lush, what is rounded and full is transitory and illusory.

Then yesterday I was walking in Berkeley, in my old neighborhood, and I saw my favorite tree. It is, I think, a Chinese pistachio. At this time of year, its leaves flame. Not all at once. They shade from green through yellow and orange to brilliant red. It may be transitory, but I need it anyway.