The Burlington artist is as well known for her social activism as for her abstracted landscapes. But it’s the latter that populate a current exhibition at Shelburne’s Furchgott Sourdiffe Gallery. Rich in palette, the oil paintings on paper are resplendent manifestations of her theme: “Hues of Summer.” Acker writes in an artist statement, “The beauty from this summer season, salted away, sustains me year-round.” The new paintings offer room, she adds, “for viewers to feel connected and uplifted.”