The Green Tree Athletic Association has been a part of the Green Tree community and Keystone Oaks for almost 50 years. We have a long standing reputation with the surrounding communities as a premier community sports organization with a state of the art complex. Through the generous donations of residents and businesses and the cooperation of the Borough of Green Tree, we are able to provide a fun-filled season for nearly 300 Green Tree boys and girls ages 4 through 18 who play baseball, softball and soccer at the borough fields including Hemlock / Aiken Ballfields, Aiken Soccer Field, Hale Park and Wilson Field.