One year on tu b’shevat someone (a second career retiree) brought Rav Soloveitchik some bokser before shiur. After chuckling, Rav Soloveitchik told a story about how Rabbi DZ Hoffman would ask on his oral semikha exams – where is Tu bshevat in the shulkan arukh? (ANS-tahanun). -- Eli Turkel