This collection covers Velva Elaine Rudd's correspondence to and with a number of individuals. There are also letters between the botanist and director of the National Museum of Natural History and Arnold Arboretum, Albert Charles Smith (1906–1999), and various correspondents. Also included are lists of plants and determinations of collections identified by Rudd and other botanists in Mexico, Venezuela, Honduras, and the southwestern and southeastern United States.

Correspondents include William Skinner Cooper (1884–1976), Carl Otto Rosendahl (1875–1956), Edgar T. Wherry (1885–1982), Henri Pittier (1857–1950), Emma Lucy Braun (1889–1971), Jason Richard Swallen (1903–1991), John W. Emmert, Delzie Demaree (1889–1987), George Hines Lowery, Jr. (1913–1978), Elizabeth Ann Bartholomew (1912–1985), Conrad Vernon Morton (1905–1972), Frank Caleb Gates (1887–1955), F.L. Bennett, Lee R. Dice, Ellsworth Paine Killip (1890–1968), R.J. Fleetwood, G.C. Fleishmann, Eizi Matuda (1894–1978), Jerzy Rzedowski (1926–2023), Truman G. Yuncker (1891–1964), Edward Franklin Castetter (1896–1978), Wallace Edmund LaBerge (1927–2013), Jesús Medardo Idrobo (1917–2010), Harold Harrington (1903–1981), Lyman Bradford Smith (1904–1997), G.F. Ledingham (1911–2006), Roland McMillan Harper (1878–1966), K.L. Clint, Carlos Muñoz (1913–1976), Gualterio Looser (1898–1982), Tobias Lasser (1911–2006), Harold Norman Moldenke (1909–1996), Richard Sumner Cowan (1921–1997), C.G.G.J. van Steenis (1901–1986), Ira Loren Wiggins (1899–1987), and J.K. Maheshwari.