Jonathan Clibborn should be applying nitrogen on his winter wheat fields right now. He should be taking delivery of seed corn and sunflower, getting his planters ready to roll by the first of April. He should be enjoying spring on his farm near Lviv in western Ukraine with his Ukrainian wife, their three boys, and their dog.

Instead, Clibborn, an Irish immigrant, is doing what nearly every other Ukrainian farmer is these days: He’s checking on relatives in the war zone, sheltering families fleeing the bombs, and struggling just to keep his farm afloat. If they don’t succeed, experts warn, not only will many Ukrainians go hungry, but so will hundreds of millions around the world, perhaps triggering the greatest food