WASHINGTON — Joseph Glauber, the U.S. Department of Agriculture’s chief economist, will retire at the end of 2014, the U.S.D.A. said, completing a 30-year career with the federal government. He was appointed chief economist in 2008. The U.S.D.A. has appointed Robert Johansson, deputy chief economist since 2012, as acting chief economist as of Jan. 1, 2015.

“No one has a higher level of credibility on issues impacting the agricultural economy than Dr.  Glauber,” said Secretary of Agriculture Tom Vilsack. “I will miss Joe’s expertise and wise counsel, and wish him well as he begins the next phase of his distinguished career.”

As chief economist, Dr. Glauber was responsible for the department’s agricultural forecasts and projections and for advising the secretary of agriculture on economic implications and alternative programs, regulations and legislative proposals, said the U.S.D.A.

In 2012, he was elected fellow of the Agricultural and Applied Economics Association, the association’s highest award, made annually to a small group of individuals who have made significant contributions to their professions.

Before becoming chief economist, Dr. Glauber was deputy chief economist from 1992 to 2007. He has also served as senior staff economist for agriculture, natural resource and trade at the President’ Council of Economic Advisers and as an economist at the U.S.D.A.’s Economic Research Service.

Dr. Glauber received his Ph.D. in agricultural economics from the University of Wisconsin in 1984. He holds an undergraduate degree in anthropology from the University of Chicago.

Dr. Johansson, Dr. Glauber’s successor in 2015, holds a Ph.D. in agricultural economics from the University of Minnesota, the U.S.D.A. said.