I found this sandal, a lefty, on Saturday, May 21, in Friendship.
The signature tread says “Birkenstock,” figuratively, and the snap says “Birkenstock” literally (but you have to zoom in pretty close to read it). I went to the Birkenstock website to find the exact model, but all of the sandals listed have buckles, not snaps.
The section of the website marked “How to Tell a Genuine Birkenstock Shoe from a Fake” suggested one possible solution to the mystery. Perhaps a genuine pair of Birks wouldn’t fade as fast as a fake, popped through at the toe and peeled away at the heel, a husk of a sandal abandoned upside-down on the asphalt on a warm spring afternoon.