06/18/2012 at 07:00 PM EDT
Growing up in San Francisco's housing projects, Kemba Shakur cherished family camping trips, where she'd sleep under the stars at Yosemite National Park.
"I loved the smell of the redwoods," she says. "It washed away the stresses of the city."
When Shakur moved to a crime-ridden section of Oakland in 1994, the former corrections officer and mom of five was shocked to discover not a single tree on her street. "Block after block of concrete," Shakur, 49, recalls. "The prison grounds looked better."
Mobilizing neighbors, family and friends, Shakur began planting elms and sycamores with money raised from grants and donations. She also incorporated a second passion – mentoring at-risk teens – and to date has taught thousands the finer points of tree maintenance.
Shakur's Urban Releaf
nonprofit has planted 7,000 trees and given another 8,000 to schools so far. Known informally as the "tree lady," Shakur and her volunteers have given lifelong residents like Renee Abdullah, 62, tree-lined streets and a renewed sense of pride.
"When the neighborhood looks good," Abdullah says, "people feel good."
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