Jerry Davis Jr., 75, a retired Army lieutenant colonel who in the 1970s started a second career as a janitorial-services business owner, died of cancer Nov. 14 at his home in Mitchellville.

Col. Davis was born in Terry, La., and was in the Army from 1943 to 1970. Among his duties was rifle company commander on the front lines in Korea during the war there and Signal Corps battalion commander in Vietnam.

He was last stationed at the Pentagon as a Signal Corps representative to the Emergency Operations Center, where he helped oversee the Army's communications systems during the urban riots of the late 1960s.

Col. Davis served in World War II, the Korean War and the Vietnam War and received the Legion of Merit, Bronze Star, Meritorious Service Medal, Army Commendation Medal and Combat Infantryman's Badge.

From 1971 to 1995, Col. Davis ran Unified Services Inc. in Washington, one of the largest minority-owned firms nationwide in terms of employees. He co-owned the company with his second wife, G. Jean Davis.

In 1986, Col. Davis acquired UNIBAR building-services maintenance firms in Ann Arbor, Mich., and was chairman and chief executive until his death.

He was a board chairman of M.U.S.C.L.E., a not-for-profit group that built housing for the homeless in Washington, a trustee of the Washington Suburban Sanitary Commission retirement fund and president of the Building Service Contractors Association International.

His marriage to Vivian Davis ended in divorce.

Survivors include his wife of 29 years, G. Jean Davis, of Mitchellville; two daughters from his first marriage, Jerry Ann Frazier of Clinton and Amelia Rosenberg of Hong Kong; a son from his second marriage, Robert S., of College Park; a sister; one granddaughter; and four great-grandchildren.