A slightly more up-beat version: A single county in Pennsylvania grows 50% of the mushrooms in the United States.
https://www.pbs.org/newshour/nation/this-small-pennsylvania-...
https://www.pbs.org/newshour/nation/this-small-pennsylvania-...
At one point they grew 90% of the worlds forced rhubarb (a special kind of rhubarb grown indoors).