Higher education’s season of retrenchment has continued into the fall semester, with public and private institutions around the country shedding programs and employees as they grapple with heavy competition for students, soaring costs and revenue constraints. The cuts often follow other, less drastic measures to plug budget gaps, such as leaving positions unfilled and reducing nonpersonnel budgets. In many cases, administrators are looking to trim programs they say are underenrolled and losing money, and instead focus where they see the most student interest.