in St. Marys, Ontario) is a Canadian botanist and cell biologist, known as one of the world's leading experts on plant root structure.
In 1996 the Canadian Botanical Association awarded her the George Lawson Medal (Category B) for lifetime contribution to botany.
Her doctoral dissertation involves histological studies of the intertidal seaweed Fucus, a genus of brown algae.
[1] She was married to the plant physiologist Martin Canny (1931–2013), who was appointed in 1986 an Honorary Research Professor at Carleton University.
[7] In the late 1990s, Martin Canny and Margaret McCully moved from Ottawa to Canberra, where he was appointed Visiting Fellow at the Australian National University's Research School of Biology.
[1] Her research topics include biology of the rhizosphere, water status of plants, and ion uptake.