By late morning the oak had a new lobby: a wide mushroom with a tiny sign that read Afternoon Guests. Beetles arrived in a polite line, left their feelers in a thimble by the stem, and only then asked the cap for a shady bed.
We asked at the kiosk. "They nod to the cap first," said the park keeper, brushing a speck of moss from the register. "If the cap nods back, the room is ready. If it waits, someone is still stretching."
A neighbor claimed the beetles had vanished for the heat. They had only gone indoors. The next day a beetle returned, tapped the thimble twice, and waited while the cap found a cooler dimple, just left of the gills.