Program with the 'Firebird Suite' is a trial by fire for young conductor

The indisposition of guest conductor Yan Pascal Tortelier threw a curve at the Baltimore Symphony Orchestra and a big opportunity at its new assistant conductor, Nicholas Hersh. This young man, judging from his resume, is at the very beginning of his career, with very little time in front of professional orchestras, but on Saturday evening at the Music Center at Strathmore in North Bethesda, he validated the BSO's judgment, handling a difficult program quite competently.