[adolgert]

Famine is caused by _local_ supply shortages. The Dust Bowl in the US was a 30% wheat shortage, but it can happen from even less shortfall if transportation is a problem. The US weaponized wheat stem rust against Russia's wheat crops during the cold war, and they were hoping the weapon would reduce total yield by 15% in order to cause major damage.

[thehappypm]

Source on that?

[jacobolus]

Kirby and Carus (2020) “Agroterrorism Perspectives”, in Mauroni and Norton, eds., Agroterrorism: National Defense Assessment, Strategies, and Capabilities. U.S. Air Force Center for Strategic Deterrence Studies. Page 9: https://www.airuniversity.af.edu/Portals/10/CSDS/books/Agrot...

> During the Cold War, the United States devised Operation Steelyard, a plan to destroy 50 percent of the Soviet Union’s winter wheat using wheat stem rust (TX) mixed with feathers (known as the M1 carrier). If the president approved Steelyard, Boeing B-29 Superfortress bombers were to drop M115 500-pound “feather” bombs filled with TX in a 60-day campaign starting in March. The Air Force forward-deployed empty M115 bombs to RAF Lakenheath and Wheelus Strategic Air Command (SAC) airbases for this purpose. The M2 two-pound containers would be airlifted to the Air Force from the TX stockpile at Edgewood Arsenal, Md. TX required an annual revolving stockpile as it had a half-life of eight months. Rye stem rust (SX) was added to augment the inventory. Steelyard was the first operational biological war plan of the United States in 1952 with a stockpile of 0.8 tons TX and SX. Secretary of Defense Charles Wilson made Steelyard a standing capability in 1954 with an arsenal of eight tons of TX and SX.

[adolgert]

This is a great reference! There is also an entry in the congressional record on declassification of the data. And 3 scientific papers. If you know more, send me a note. I worked in the area of rust spread and have always wanted to learn more about this.

[jacobolus]

I only know what I found in 10 minutes of web searches, sorry.

[jacobolus]

Also see https://en.wikipedia.org/wiki/M115_bomb

[adolgert]

I didn't mean to drop that comment and leave. I learned about the weaponization from Ft. Dietrich people. The group that worked on this is long since retired. They published three papers around 1950, as three parts, that are about 1. the largest study of spread of rust fungus outdoors 2. storage of rusts and 3. response of rust to weather. All useful for stopping rust on a crop. And I see someone contributed references that are more direct than my scientific ones. I was working on prevention of rust spread.