Ada Hayden (1884-1950) was born on August 14, 1884 in Ames, Iowa. She earned a Bachelor of Science (1908) and Doctor of Philosophy (1918) degrees at Iowa State University. Hayden also earned a Master of Science degree (1910) from Washington University in St. Louis. Hayden was the first woman to earn a Doctor of Philosophy degree at Iowa State University.
She was an Instructor (1910-1918) in Botany, an Assistant Professor (1919-1950) of Botany, and named Curator of the Herbarium (1947-1950). Photographing and illustrating plants was a specialty as well. During her time at Iowa State she added more than 40,000 specimens to the herbarium.
In 1988, the Iowa State University herbarium was named the Ada Hayden Herbarium in honor of its former curator. Hayden was an avid conservationist who worked to have natural prairies in the state set aside as preserves. After her death a prairie preserve in Howard County, Iowa, was named the Ada Hayden Prairie Preserve by the Iowa Conservation Commission.