Patsy Cannon Boyce, civic volunteer and businesswoman

She was “one of the people on whom I most relied when I began my work as a state representative for advice on how to work to improve the quality of life in downtown Boston,’’ Representative Barney Frank, a Massachusetts Democrat, said in an e-mail to her family.

“She was a pioneer,’’ he wrote, “in making urban environmentalism a reality, to the great benefit both of the city neighborhoods she fought for and to the environmental movement itself.’’

Mrs. Boyce, who aided projects including redesigning the courtyard of the Boston Public Library, the upkeep of Commonwealth Avenue Mall, and the maintenance of the Esplanade, died of congestive heart failure and complications of dementia Aug. 10 in her home in Sun City West, Ariz., where she had wintered for many years. She was 77 and had spent every summer for decades in Gloucester.

In his e-mail, Frank called her “a person of great commitment, great energy, and a wonderful temperament.’’

“Being in her company,’’ he said, “meant you would simultaneously be put at ease and challenged, and most of all, instructed in a very inspiring way.’’

Her son, James Cannon Boyce of Boston, said that from the 1970s to the ’90s, his mother “was one of the most active residents in the Back Bay.’’

“She was instrumental in the founding and growth of The Garden Club of the Back Bay, for which she served as president for many years,’’ he said. “She served on both the building committee and vestry of Trinity Church in Copley Square. She supported both the Neighborhood Association of the Back Bay and the main branch of the Boston Public Library on Copley Square.’’

Trish McNamara, a niece in Phoenix, said she was “a thin and elegant woman with reddish brown hair and a sparkle in her eyes.’’

Well into her 70s, she audited classes in Boston University’s Evergreen program, for those 58 and older, her son said. “She studied everything from Chinese to English literature.’’

Mrs. Boyce introduced her family to activism and encouraged her son to participate in activities to which she was drawn.

“Growing up in the Back Bay with my mother meant there was always something to do or someone to help,’’ her son said.

Born in Bellingham, Wash., she was one of four daughters of George Frederick and Carolyn Ruth Cannon.

She graduated from Bellingham High School and from Gonzaga University in Spokane, Wash., with a nursing degree, before working for Pan Am.

She traveled the world with Pan Am and with her three sisters. McNamara said her aunt worked for Pan Am for several years and “would bring back gifts from China and Japan and have stories to tell.’’

Her son said she flew several prestigious routes for Pan Am, including the first commercial flight over the North Pole and on the airline’s special charters that served leaders and monarchs from around the world.

After leaving Pan Am, she was social director for the S.S. Brazil cruise ship. Mrs. Boyce also was a secretary for Johnson during the future president’s political career.

In the early 1960s, she married James E. Boyce, who became president of an international consulting firm he established, and they moved to Massachusetts.

Mrs. Boyce returned to college and took graduate studies in landscape design at Radcliffe College.

“My mother was one generation early in terms of women in business,’’ her son said. “She couldn’t really have a business career, so she created her own path and her own career.’’

Her husband died in 1984 while on a business trip to Singapore, and his wife ran the company for 15 years, traveling to Asia twice a year until closing the business.

In 1987, she married Joseph Sidlovsky. She continued to use Boyce as her legal name, however.

Before she died, Mrs. Boyce fulfilled a wish, her niece said. She had been to six of the seven continents until several years ago, when she and a stepson went to Antarctica to complete her visits to all seven.

In addition to her husband and son, Mrs. Boyce leaves two sisters, Carolyn Cannon McKinnon and Neila Cannon McNamara, both of Sun City West, Ariz.; four stepchildren, Mark Sidlovsky of Charlotte, N.C., Ann Marie Tate, of Cincinnati, Marshall Boyce of Phoenix, and Stuart Boyce of Boulder, Colo.; and two grandchildren.

A memorial service will be held at 10 a.m. tomorrow in Trinity Church in Copley Square.

Mrs. Boyce also contributed articles to the Globe occasionally, including one for the Valentine’s Day edition of the Home and Garden section praising the virtues of roses.

“My mother cried when my father brought her roses,’’ she wrote. “She put them in a container and sort of fluffed them up. They were not arranged. They were beautiful. When their heads started to droop, she used Scotch tape and toothpicks to hold them up. When they lost their petals, she saved them for a potpourri in the kitchen. We enjoyed them with her.’’

That love of roses became part of Mrs. Boyce’s life.

She “mentioned roses to a date once,’’ she wrote. “He looked at me as though I were deranged. I thought I might find him interesting, but changed my mind.’’

Gloria Negri can be reached at g_negri@globe.com.