Forrester spent much of her youth tending to the asparagus, cucumbers, and tobacco on her family’s Massachusetts farm. With an imbued appreciation for plant life, she once said her goal as an artist was to capture nature’s vitality on paper. "The subject of my work is always growth - how trees and plants bulge and stretch and open." Forrester moved to the Washington area in the early 1980s and frequently painted landscapes around the District, including at the National Arboretum. "I think I know almost every tree and flower there," she said in 2009. "No preliminary drawings, no photographs are ever involved. I sit on the ground using a cardboard box to lift my paper and tilt it slightly toward me." In other words, Forrester was a plein air (outdoor) painter who worked directly in nature rather than in her studio.