The papers of B. O. Wolden consist primarily of correspondence that spans some sixty years. Wolden corresponded with some of the nation's most respected botanists including Henry S. Conard and R. I. Cratty. The remainder of the collection is comprised of Wolden's notebooks, in which he recorded such things as weather, appearances of birds, observations of flora, etc. He also kept notes about the history of Wallingford, Iowa.