“The colors were so incredible, I just couldn’t leave,” she said. “And then in November, the world looked like one of Wolf’s pastels.”

Color ebulliently deployed was at the heart of Ms. Mason’s work, and it was one of the things that set her apart from her mother, the abstract painter Alice Trumbull Mason. Whereas her mother’s paintings often featured highly structured, quasi-geometrical forms, Emily Mason’s vibrant works, generally in oil, explored the varieties of a single color, or the play between multiple colors, in joyously free-form fashion.

“Hot Item” (2013) is a furious collection of reds, tantalizing but also somewhat ominous. “Summer Harvest” (2018) is an inviting composition in yellow and gold that seems to radiate warmth.

Her method was not to plan out a painting in advance, but to start working and see where it took her. She might begin by laying a blank canvas on the floor, pouring paint on it from a tin (she sometimes recycled cat food containers for this purpose), tilting the canvas to and fro to let the paint run about, then adding colors, eventually setting it aside and resuming work later. It was a process, she liked to say, of “letting a painting talk to you.”