The original collection was assembled for the World's Colombian Exposition of 1893 in Chicago. Over 10% (1438 items) of the economic botany specimens date from this exposition with especially rich representation from the national exhibits of British Guiana, the Philippines, Japan, Brazil, Burma and India. These collections can essentially be considered the historic beginning of the Botany Department. The majority of collection acquisition occurred during the four decades following the World's Colombian Exposition.
- Paris Exposition (1901)
- Louisiana Purchase Exposition (1904)
- Panama-Pacific Exposition (1915)
US government sources:
- crop cultivar samples
- fiber samples of raw flax and processed linen
Foreign institutions or governments:
- India Forest Research Institute
- Philippines Board of Education
- Australian Technological Museum
Commercial or Industrial sources:
- Fritzsche Brothers, Inc., New York
- Chicago Varnish Co.
- Archer-Daniels-Midland Co.
- S.B. Penick & Co.
- Parke, Davis & Co.
- Frederick A. Stokes & Co.
Field Museum sponsored expeditions:
- Mrs. T. B. Blackstone Expedition 1908-1910 (Eastern Tibet)
- Mulford Biological Exploration 1921 (Bolivia)
- Stanley Field Expedition 1922 (British Guiana)
- Marshall Field Expedition 1922-1923 (Peru)
- Marshall Field China Expedition 1923
- Marshall Field Brazil Expedition 1926
- F.M.-Oxford U. Joint Expedition 1926, 1928, 1942 (Iraq)
- Marshall Field Amazon Expedition 1929-1930 (Brazil, Peru)
- F.M. Venezuelan Expedition 1942
The collection is currently housed in a compactorized storage unit that was designed to meet the unique demands for these objects. The collection is named in honor of Timothy C. Plowman, former curator of Botany, who was instrumental in obtaining funds to preserve this collection.