The station itself, well west of the yard went in '64 when they did the World's Fair. The yard itself - good question! There may be a date here in the archives of this site, the yard was discussed by retired employees quite a few times but the answer eludes my attention span. If you go to Arrt's page,
http://arrts-arrchives.com/wstone1.html" onclick="window.open(this.href);return false; and also hit the second page of this, you'll see definitely until 1978. I know personally it was gone by the mid '90s and the sumac was pretty thick growing where the switch curved away from Shea Interlocking. Steve's page also has quite a bit of info about the old branch too:
http://www.trainsarefun.com/lirr/whites ... estone.htm" onclick="window.open(this.href);return false; and also
http://www.trainsarefun.com/lirr/freightsidings.htm" onclick="window.open(this.href);return false;, scroll part way down to the Corona Yard post.