Cornell University has digitized the contents of the Census of Agriculture from 1840 to 2002. IPUMS NHGIS has data from 1840-1950.
United States census of agriculture: 1950, Bureau of the Census, Washington] U.S. Govt. Print. Off., 1952. 5 v. in 64 pts
Contents:
v. 1. Counties and state economic areas. 34 pts.
v. 2. General report. Statistics by subjects.
v. 3. Irrigation of agricultural lands. 18 pts.
v. 4. Drainage of agricultural lands.
v. 5. Special reports. 10 pts.
The 1950 censuses, how they were taken; population, housing, agriculture, irrigation, drainage. Prepared in the Office of the assistant Director for Statistical Standards, Statistical Reports Division, under the supervision of Morris B. Ullman, United States Bureau of the Census, Washington 1955.
Portfolio of United States census maps, 1950. A selection of maps used in the publications of the 1950 censuses of population and agriculture. Prepared under the supervision of Clarence E. Batschelet, chief, Geography Division, United States, Bureau of the Census, Washington, United States Govt. Print. Off., 1953.
Contents: pt. 1. Population.--pt. 2. Agriculture.
Oversize HA201 1950 .A41q (DOCSC) Decennial Census, Firestone Library.