A night walk in the woods turns into a small lesson in restraint. The speaker finds foxfire, the faint glowing fungus on rotting wood, and takes a piece home in a pocket, meaning to share it. Once back, though, he can't bring himself to mention it. Showing it off like a trophy feels wrong for something so quiet and hidden. By the next day the glow is gone, and the nubbin looks like a shriveled dead ear on his computer monitor, a nice joke about how magic fades once it's taken out of its setting.
The short three-line verse at the end shifts the mood. A dream of sickness gives way to waking up well, and then a tree full of birds. The poem seems to suggest that the real charm lies in noticing and letting things be, not in owning them. The tone is hushed, curious, and gently humble, with a touch of dry humor.