The Ace of Spades Hitchhiker was found! In the first report back to me, Eagle Bob and Teapot Marie wrote that they found it in the Lock Rock box. It seems that it was transported in June by ARC & Sassy from its original spot on the Perkiomen Trail (where I planted it in April). Thanks again, Marie and Bob, for letting me know that my first hitchhiker is still out there somewhere!