That would be a good question to ask the Vancouver Public Library, who has a room named after her! Alma Blanche VanDusen (nee Heal) was the wife of Whitford Julian VanDusen, lumber magnate of MacMillan Bloedel and philanthropist. He helped to oversee the establishment and incorporation of the Vancouver Foundation, and the VanDusen Botanical Garden is named in honour of him.
Alma Blanche Vandusen passed away on December 13, 1969 at age 81 (via BCArchives). That means she was born around 1888, and is therefore almost as old as the City of Vancouver itself! See this page for more information about her husband, WJ VanDusen.
Why do you ask? Did you find some artwork attributed to her?