Bernie Boston, the photojournalist who captured the iconic image of a young Vietnam war protester placing a flower in the barrel of a rifle held by a National Guardsman, died Tuesday at his home in Bayse, Va. He was 74.

The photo known as “Flower Power” became Boston’s signature image and earned him acclaim in the world of photojournalism. Taken during the October 22, 1967, anti-war march on the Pentagon, the photo was a finalist for the Pulitzer Prize.

“Flower Power is one of those quintessential images,” a spokeswoman from the Rochester Institute of Technology, which houses Boston’s archives and in 2006 presented an exhibition of his works, Therese Mulligan, said. “It sums up that period, how a lot of people feel about the ’60s.”

Boston was a photographer for the now-defunct Washington Star when anti-war demonstrators approached the Pentagon. Positioned on a wall at the Mall Entrance to the Pentagon, Boston watched as a lieutenant marched a squad of guardsmen into the sea of demonstrators. The squad formed a semi circle, their guns pointed at the demonstrators. Boston was ready for anything that might happen.

“And this young man appeared with flowers and proceeded … (to) put them down the rifle barrel,” Boston told National Public Radio in 2006. “And I was on the wall so I could see all this and I just started shooting.”

The resulting photograph is a rich, nuanced image of a chapter of American history.

Back at the office, Boston’s photograph received a lukewarm response. It was not prominently displayed in the newspaper.

“The editor didn’t see the importance of the picture,” Boston said later.

“We buried it,” Boston told NPR. “I entered it in contests, and it started winning everything and being recognized.”

Born May 18, 1933, in Washington, D.C., Boston grew up in McLean, Va., and was a photographer for his high school newspaper and yearbook. In 1955, after earning a degree in photography from the Rochester Institute of Technology, he spent three years in the Army. He joined the staff of the Dayton Daily News in Ohio in 1963 and three years later joined the staff of the Washington Star, where he remained until the paper folded in 1981. The same year he photographed Flower Power, Boston shot a portrait of former Black Panther H. Rap Brown. He captured images of the civil rights movement, including a portrait of the Reverend Martin Luther King Jr. during his Poor People’s Campaign, and other history-making events of the ’60s. Boston also photographed every American president from Harry Truman to Bill Clinton.

In 1981 the Los Angeles Times hired Boston as a staff photographer in its Washington D.C. bureau. Six years later, Boston was a finalist for a Pulitzer Prize in the spot news category for his photograph of King’s widow, Coretta Scott King, at the unveiling of a bronze bust of King.

Boston and his wife, Peggy, moved to Bayse in 1994, where he published and she edited the Bryce Mountain Courier.