Just an FYI, no plants ever add minerals to the soil. Whenever plant material is removed from land, minerals are also removed. The organic material comes from the air. You must add rock dust to actually add minerals. That's why Yellowstone erupting might actually help farmers on the fringes of the fallout.

"Rock dust is a natural, slow-release soil amendment used to remineralize depleted soils. Finely ground from volcanic rocks (like basalt) or glacial deposits, it provides essential trace minerals, stabilizes pH, and enhances water retention and microbial activity for long-term soil health." - - Google