Levi Strauss & Co has elected T Gary Rogers, the boss of a successful ice cream firm, as the chairman of its board of directors.

Rogers, a director at the denim firm since 1998, retires at the end of this month as chairman of the board and chief executive officer at Dreyer's Grand Ice Cream after 30 years with the company. His election at Levi's is effective from February next year.

Rogers' appointment means the chairman's role passed to an executive with no family ties to founder Levi Strauss for the first time in 155 years, reported local paper the San Francisco Chronicle.

Rogers replaces Robert D Haas at Levi's, who is retiring after 18 years as chairman but will remain on the board as a director with the honorary title of chairman emeritus.

Haas said: "After 35 years with the company, including 15 years as its chief executive officer, I look forward to being able to devote more time to other aspects of my life, including my family and our philanthropic interests."

Rogers purchased Dreyer's Grand Ice Cream with his business partner in 1977 and transformed it from a small, regional ice cream operation into a large US operation, a statement noted.

He said: "Of all the boards I've served on over the years, I have never observed a chairman manage a board so effectively. Bob leaves very large shoes to fill, but I am looking forward to working closely with LS&CO. management and my board colleagues to build on this impressive legacy."