About: http://webisa.webdatacommons.org/49116641

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Assuming a tree is a playing surface, it is not OB unless declared OB. In most cases I do not think a player has time to make a tree a playing surface but I have not read that it is technically prohibited.
http://www.w3.org/ns/prov#wasQuotedFrom	sndg.org