In 1969, Jordan moved to Argonne National Laboratory where he continued to study radioactive pollution from nuclear power plants around Lake Michigan.

In 1974, he led a project for the University of Georgia near San Carlos de Río Negro in the Amazon Region of Venezuela.

During this time he focused on determining how forests of the Amazon survived on the nutrient-poor soils and could even flourish and support shifting cultivation.

His research showed that nutrients from decaying organic matter on the forest floor recycled directly back into the roots of living trees.

In 1993, Jordan acquired a farm near Athens Georgia that had once been part of a pre-Civil cotton plantation and began research on more sustainable ways to manage organic agriculture.