Sharp-eyed visitors to the Traverwood branch of the Ann Arbor District Library–or readers studying the cover of this month’s Observer–may wonder about the names written on a ceiling beam. The beam is supported by several ash tree trunks, all encircled with the winding trails of the emerald ash borers that killed them. High up, where four trunks meet the beam, the names Jack, Phillip, Beatrice, and Lily are printed in black marker.

“They’re the names of the children of the man who designed the wood interior, John Yarema,” explains AADL director Josie Parker. As a child, Parker herself sometimes left similar legacies: “My father was a builder, and he sometimes let us put our names and handprints in wet concrete–though it was usually in places that were going to be covered up.”