Early Military Testing
These documents and photographs were released through the Freedom of Information Act after they first came to public light by way of mass classified document leak posted by WikiLeaks. 

These documents cover a time period from the late 1950s up to the early 1970s in which secret military testing was being done on a genus of parasitic fungus known as Cordyceps.
Testing in the 1950s focused on the invasive growth of the fungus, and how to optimize its potential to immobilize its victims. By way of a aggressive testing, a genus of fungus was discovered that was quite effective at de-mobilizing a wide range of motorized vehicles if given the appropriate time to germinate.
Beginning in 1962, experimentation was being conducted on the Cordyceps spores, focusing on speeding up the germination process. By 1967, a cultivated spore was developed that cut the germination time down from two months to just under one week (5-6 days). There were serious concerns voiced at the time around the containment of such an aggressive fungus and what would happen if a containment breach were to occur.

Testing and development continued until Febuary 19th, 1971 when President Nixon suddenly shelved the project and all documentation was sealed.