Counting Crows [ tickets ], who were scheduled to kick off their U.S. run later this month, have postponed the outing's first four dates so that frontman Adam Duritz's vocal chords can recuperate.

"Unfortunately, we are going to have to reschedule some of our early spring touring plans," the group said in a message posted at its website. "Due to our extensive touring over the last year, Adam's vocal chords have become extremely strained. With that said, great amounts of vocal-rest have been medically advised."

The affected shows were set for March 25 in New Orleans, March 27 in Tampa, March 29 in Orlando and March 30 in Boca Raton. Make-up dates have not yet been announced.

The postponements mean that the group's outing is now scheduled to kick off in Iowa on April 3, and dates have been added through the end of that month.

The spring outing is the latest leg of Counting Crows' ongoing tour behind last July's "Hard Candy." The album features the group's latest hit, a cover version of Joni Mitchell's "Big Yellow Taxi." The cut--which is a hidden track--also features Vanessa Carlton.

This summer, Counting Crows and recent GRAMMY winner John Mayer plan to head out on a co-headlining tour, though no dates have been revealed.