M. K. Jessup, Carl La Rue, and James Weir in Brazil on an Expedition for the U.S. Department of Agriculture, 1923

In 1923, threatened by a rising English rubber monopoly, President Herbert Hoover ordered an expedition to study the possibility of growing rubber in the Amazon. Members of the trip included photographer Morris K. Jessup, University of Michigan botanist Carl D. LaRue, and plant pathologist James Weir. Henry Ford would later draw on the expedition's findings when planning his rubber plantations in the Amazon.