Hi, Anne — What you found in DC is a fruit from the Osage Orange tree (Maclura pomifera). Osage Orange, also known in the Midwest as Hedge or Hedge Apple, is native to the south and Midwest US, and was often planted as hedges or as windbreaks on the Great Plains.
If you still have the fruit, give it a squeeze or scratch the skin and take a sniff; it has a pleasantly spicy smell. Deb Sent from my iPad -- The LincolnTalk mailing list. To post, send mail to Lincoln@lincolntalk.org. Browse the archives at https://pairlist9.pair.net/mailman/private/lincoln/. Change your subscription settings at https://pairlist9.pair.net/mailman/listinfo/lincoln.