A summer concert series begins this week and continues every Wednesday evening through Aug. 4 on the Sherborn Library green. The free concerts, sponsored by the Friends of the Sherborn Library, begin at 6:30 and run until 8:30 p.m. Residents are encouraged to bring a picnic and blanket to enjoy the local musicians. This week’s band is the Infractions, a horn-driven ensemble covering six decades of music from Duke Ellington to Dave Matthews and Maroon 5. Group Therapy, a 10-piece band with a range of music from country to rock to rhythm and blues, plays on July 18; Something with Digby, which covers songs by the Beatles, Rolling Stones, Brad Paisley and others, plays July 25; and Guys in Tuxes, a seven-piece orchestra that bases its set completely on requests, plays on Aug. 4. In case of inclement weather, call the library after 4 p.m. for cancellation information.