During World War I, he served as a seaman in the United States Navy.
[1] After his father retired from the company, Edgar took over the leadership of Monsanto in 1928.
He published the book Prairie Wings, called a "classic study of American wildfowl in flight," and participated in the production of several nature documentaries, including some from Africa produced in cooperation with Kenyan guide Donald Ker.
Edgar M. Queeny Park in Town and Country, Missouri is named after him.
In 2011, Queeny's Arkansas farm and family estate, Wingmead, was listed on the National Register of Historic Places.