Thoreau MacDonald (1901-1989) was born in Toronto, Ontario. His formative years were spent in rural areas near High Park, and in Thornhill, north of Toronto. Thoreau's drawings and writings about the wild plants and animals native to these regions reflect his deep concern for and support of nature conservation.

Thoreau created thousands of images including pencil sketches, pen and brush drawings, stencils, linocuts, woodcuts, silkscreens, watercolours and oils. He is perhaps best remembered for creating detailed line drawings of natural objects set within their stylized habitats.

Under his Woodchuck Press imprint, Thoreau designed and published sixteen books or booklets of his own work. His drawings and calligraphy have adorned hundreds of books written by others most notable among which are Flint and Feather, E. Pauline Johnson, 1924; Lyrics of Earth, Archibald Lampman, 1925; The Chopping Bee and other Laurentian Stories, Brother Marie Victorin, 1925; West by East, J. E. H. MacDonald, 1933; Maria Chapdelaine, Louis Hemon, translated by W. H. Blake, 1938; Anne of Green Gables, Lucy Maud Montgomery, 1942; and David and Other Poems, Earle Birney, 1942.

Thoreau MacDonald was the son of Group of Seven member J. E. H. MacDonald. His work is found in the National Gallery of Canada in Ottawa, Hart House at the University of Toronto, the Art Gallery of Ontario, and the McMichael Canadian Art Collection amongst others.