Byrd's death was reported by the Winchester Star, a newspaper published for generations by his family. The newspaper said he died at his home in Winchester.
Byrd was a member of an old Virginia family. His father, Harry F. Byrd Sr., served in the Senate for 32 years and Richard Byrd, the naval aviator and polar explorer, was his uncle.
In 1965, when the elder Byrd resigned from the Senate for health reasons, his son was appointed to succeed him and won a special election in 1966 as a Democrat. But four years later, Byrd quit the Democratic Party, refusing to sign an oath that he would support the 1972 presidential candidate, whoever it might be.
Byrd won elections in 1970 and 1976 as an independent, although he continued to caucus with the Democrats. In the Senate, Byrd was known as a fiscal conservative, whose major legislative achievement was a law mandating the federal government balance the budget. He was also known as a hard worker, showing up for 96 percent of the roll calls.
Before he joined the Senate, Byrd had been a naval officer in World War II, publisher of the Star and an 18-year member of the Virginia Senate.
Byrd's family was also in the apple business. He served as a page at the first Shenandoah Apple Blossom Festival in 1924 and grand marshal at the most recent one.
His wife, Gretchen Thomson Byrd, was a former queen of the festival.