A well-known civic activist was found shot to death Friday night in her home in the Powelton section of Philadelphia, police said Saturday.

Friends identified her as Winnie Harris, 65, the acting executive director and longtime volunteer coordinator at UC Green, a West Philadelphia-based group that plants and tends trees.

A neighbor who saw an open window in Harris' home and wondered if something was amiss called Harris' nephew, perhaps Thursday or Friday, police said. The nephew went to Harris' home Friday and couldn't get in. Police were then alerted.

About 8:20 p.m. Friday, officers arrived at Harris' home on the 300 block of North Holly Street. There, they found her unresponsive in a second-floor front bedroom, with a gunshot wound to her abdomen. Medics pronounced her dead at the scene at 8:57 p.m. Friday. 

The motive for the shooting was unknown. No arrest has been reported.

Joe Shapiro, 69, of University City, a longtime volunteer at UC Green, said he last saw Harris on Wednesday morning at the nonprofit's office at 4601 Spruce St. He was returning shovels and trowels that he borrowed for a project. Everything seemed normal with her, he said.

He said Harris worked at UC Green for about 18 years as a volunteer coordinator, and then about a year ago started doing double duty, working as its acting executive director as well.

Shapiro said he heard that Harris didn't show up at a Thursday morning community group meeting, which she usually attended. That also raised red flags.

Elizabeth Waring, 66, a close friend of Harris' and a volunteer with UC Green, said Saturday night that she was the person who called police after another neighbor had noticed that a second-floor window of Harris' house had been open for two days and Harris' nephew couldn't get into the house on Friday.

She, other neighbors, and Harris' nephew were at the house when police arrived, Waring said.

"I was shocked," she said. "I was very upset because I thought maybe she had a heart attack or something rather than it being a homicide."

"Winnie was a well-loved person, a community organizer" who cared about "turning the world green," Waring said. "She was very well-loved. She will be very missed."

Ed Datz, chair of the board of UC Green and the executive director of real estate at the University of Pennsylvania, said in an email that everyone at UC Green is "deeply saddened by the news of Winnie's death. She was an extremely dedicated employee of UC Green." 

"During her tenure, she oversaw many community greening projects with the assistance of a committed group of community volunteers," he wrote. "Winnie was extremely proud of the Green Corps, which provided local high school students environmental education and leadership training during the summer months. Winnie worked tirelessly for the organization for well over 10 years." 

Johannah Fine, 71, of West Philadelphia, a volunteer at UC Green, said Harris majored in interior design and received her undergraduate degree from Drexel University. Harris always had a get-it-done attitude and was a mentor to a lot of people "from teenagers to the old crankies, 14-year-olds to the 70-year-olds," said Fine. 

Stephen McCoubrey, 65, of University City, another longtime volunteer and a consulting landscape architect with UC Green, said Harris "was generous and she had a great sense of humor. She worked tirelessly."

Mark Wagenveld, 72, another UC Green volunteer who is also a former suburban Inquirer editor, said in an email: "Winnie was the master of detail who organized scores of tree plantings on Saturday mornings in West Philadelphia for many years. She hauled the tools to the main gathering site, and dispatched the volunteers and their tools and trees in all directions.

"The volunteers always arrived to find snacks to get them started, and never went home without pizza and drinks. No tree planting was ever truly over for Winnie until every last shovel, broom, and pickax had been brought back from the neighborhoods, accounted for, and returned to the tool shed. Over the years, she must have been involved in planting thousands of street trees in front of homes and around schools and playgrounds."

Harris, Wagenveld also recalled, "always wore a denim jacket and a kerchief for her hair."

Neighbors of Harris' expressed shock Saturday afternoon that anyone would kill her.

One woman, Kia G., 57, who did not want to give her last name, had tied three red, black, and silver helium balloons that said "I Love You" or "Love You" on the lamp in front of Harris' well-appointed two-story brick rowhouse with a purple door, on narrow Holly Street, near 41st Street and Powelton Avenue. She also put one red rose in the lamp fixture.

"She's been a pillar in this community," Kia said during an interview. "Winnie, to me, is a legend in this community."

"She tried to show us a better, greener life," added Kia.

Neighbors spoke about how Harris planted trees on her block and other blocks. She set up a community garden on her block. On warmer days, neighbors would see her up bright and early, tending to the garden.

A few neighbors said they hadn't seen her for days, but didn't think it was odd because of the cold weather.

Harris lived on the block for about 40 years — by herself in recent years. She had raised a daughter, a niece, and a nephew there, Kia said. "She was always so happy and proud of being a single parent," she said.

"I can't fathom in my mind who would dislike her," said Kia, clearly devastated. "She was a good-spirited, community person."

Another neighbor, Janaya Caple, 25, said: "Ms. Winnie, she lived here forever." She also spoke of how Harris maintained the community garden on the block and had raised a nephew who had moved out of the house perhaps more than a decade ago. Caple said another neighbor had mentioned not being able to get in contact with Harris for days.

"She was very proud of where she lived," said another 25-year-old neighbor, who did not want to give her name. A 27-year-old man who lives with this woman said Harris would push people to go to meetings on urban agriculture. She would often talk about how many trees she planted each day, said the man, who also declined to give his name.

"She swept the block up and did the garden," said another neighbor, Larry Bond, 60.

Kia said the last time she saw Harris was about two weeks ago, in passing on Powelton Avenue. Another neighbor last saw her on Monday, when she was taking out her trash and recycling, Kia said.

"We love her, we miss her," said Kia. "People cared about her."