Based in Toronto for most of her life, Howard found subject matter nearby at Lake Simcoe, Stoney Lake, the Albion Hills and the Toronto Islands. She also travelled frequently to the East Coast. However, she was never concerned with portraying the specifics of a particular place: rather, she observed natural phenomena with the greatest attention in order to express a more universal experience.
In her introduction to the catalogue for Howard's 1980 solo exhibition The Event in the Mind, sculptor Rebecca Sisler wrote: "Barbara Howard's work defies specific slotting, although we sense her recognition of the heritage left by great masters, Turner being the most obvious. But she draws and paints in direct response to her own muse and as such cannot be aligned to any particular art movement ... for in common with other maverick artists throughout art history, her work, although bound to no age, is relevant to all."