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Ralph M. Caldwell papers

 Collection — Box: Communal Collections 17, Placement: 25
Identifier: MSF 80

Scope and Contents

This collection consists of one folder containing three articles written by Ralph Caldwell.


  • 1934 - 1943


Language of Materials

Collection materials are in English.

Access Information

This collection is open for research.

Copyright and Use Information

Copyrights held by Purdue University or original creator/publisher. Consult with Purdue University Archives and Special Collections prior to reproduction of materials.

Biographical Information

Ralph Merrill Caldwell was born June 27, 1903, in Brookings, South Dakota. He graduated from what is now South Dakota State University with a Bachelor of Science (B.S.) degree in Agronomy in 1925. He earned a Master of Science (M.S.) degree in Botany in 1927 and the PhD in Plant Pathology in 1929, both from the University of Wisconsin. He was married to Margaret Dunlap and they were the parents of one daughter, Janet (Mrs. R. W. Storts).

Caldwell served a two-year stint as Wisconsin State Leader for Barberry Eradication (1928-1930). In 1930 he came to Purdue University as an Associate Plant Pathologist in the U.S. Department of Agriculture (now the Agricultural Research Service) in charge of wheat leaf rust research.

Dr. Caldwell resigned his position with the USDA in 1937 to become Head of the Department of Botany and Plant Pathology at Purdue University (1937-1950), a position he held for 17 years, while remaining a USDA Collaborator. In 1954, Caldwell returned to full-time research and cereal breeding. On several occasions, Dr. Caldwell served as consultant to the international wheat breeding program of CIMMYT, working in Mexico with scientists and graduate students from throughout the world. Following his retirement on June 20, 1971, Caldwell served as wheat breeding consultant to the DeKalb Seed Company.

During his career, Dr. Caldwell authored over 40 journal articles and numerous reseach bulletins. He was a member, fellow, and held leadership positions in the following professional societies: American Phytopathological Society, American Society of Agronomy, Crop Science Society of America, American Association for the Advancement of Science, and Indiana Academy of Science. He received the Crops and Soils Merit Award of the Indiana Crop Improvement Association in 1954 and the Purdue Agricultural Alumni Association's "Certificate of Distinction" in 1965.

Caldwell died November 2, 1976, in College Station, Texas.
Sources: "Caldwell, Ralph M. (Ralph Merrill), 1903-." Library of Congress Name Authority File. />

Schafer, John F. "Pioneer Leaders in Plant Pathology: Ralph M. Caldwell." Annual Reviews of Phytopathology. Vol. 31. (1993): 32-41. />

Athow, Kirk L., Ralph J. Green, Jr., John F. Schafer, and Gregory Shaner. "Ralph Merrill Caldwell, 1903-1976." Phytopathology. Vol. 67, No. 11 (1977): 1317. />


0.025 Cubic Feet (One folder)


Collection materials are arranged chronologically.

Processing Information

Material has been housed in acid-free folder and box.
Ralph M. Caldwell papers
In Progress
Amanda Rumba and Archives Staff
Description rules
Describing Archives: A Content Standard
Language of description
Script of description
Language of description note
Edition statement
Second edition. Collection description first completed 2010-11-07 by Archives Staff.

Revision Statements

  • 2020-04-14: Collection description updated by Amanda Rumba to align with data entry standards.

Repository Details

Part of the Purdue University Archives and Special Collections Repository

504 Mitch Daniels Boulevard
West Lafayette Indiana 47907 United States