The weather's highly variable these days. Few people dispute that, however much they disagree over causes. Weather becoming more variable is a problem for farmers -- and when farmers start to have problems, the rest of us has better worry: nobody's growing corn or cattle in a factory, at least not yet.*
One problem is that cereal grains are nearly monocultures, There's not a lot of diversity within each type. Specific varieties of corn, wheat and so on are bred to be disease, insect and whatevericide resistant, to grow to a uniform height, and to grow under specific conditions. (The late "Farmer Frank" James waged a long fight with commercial seed
companies, since he grew his own stuff from his own seeds gathered the previous year and they were sure he was cheating; he wasn't. What he was, was stubborn. As farmers often are.)
It wasn't always that way. Prior to (highly) mechanized farming,† there was a lot of genetic variation even within the broad varieties of grain. It gave the plants as a whole better odds of getting through droughts or prolonged wet weather, cold spells or baking heat. But that variety wasn't so great for harvesting equipment, nor for maximizing yield for a given situation.
But we're human beings. Our species lives in the space between chaos and order, bouncing from one to the other. When enough of us face a challenge, we'll try all the possibilities. Up in the Pacific Northwest, small-scale "artisanal" farmers and bakers and
a university lab full of bread enthusiasts are trying things -- like greater variety. Like whole wheat.‡
And these days, you can grow that more-varied stuff with commercial equipment. Farming machines are better, smarter, more able to deal with randomness. --At a price.
Greater variety means greater resilience. But it also make it more likely farmers will need new machinery. It means seed companies are going to have to look for a broad spectrum of resistances and introduce new and more internally-varied lines of crops, and they do so love their matched-up seeds, weedkillers and pesticides that work together as smoothly as a key in a lock -- and are locked into tight genomes that will fall in lockstep unison if a new bug or plant virus emerges, or if growing conditions change too much.
As a culture, we can get there from here, moving from vulnerability to resilience. And if the past is any guide, we probably will. But it may not be especially easy, and it sure won't be cheap. And there's the chicken-and-egg: it's not going to happen out of the blue. Events drive changes; changes drive events.
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* They are growing chicken, at least on a small scale. State governments have not reacted well to Chicken Of The Beaker, and if you were hoping to try a platter of chicken nuggets that never clucked, don't be in a hurry.
† Let's not kid ourselves: farming has always been about mechanization. Rows replaced random planting; Sharp sticks replaced poking holes in the dirt with a finger, plows replaced sharp sticks and underwent continuous improvement. Oxen replaced people; horses replaced oxen -- but only after a proper horse collar was invented; horses gave way to steam, steam to internal combustion, and some bright guy has already shingled the house and barns with solar cells to keep his electric tractor charged up while laughing at diesel prices. In dim prehistory, it was apparently sufficient for early farmers to see a wheeled wagon from afar to spur them making their own versions. Humans have been cheating Malthusan limits for centuries by getting better and better at growing food though better technology.
‡ I grew up in a household where there was always whole wheat bread -- usually Roman Meal -- next to the white bread, and most of us preferred it. It'll hold up to a proper sandwich better than store-bought white bread, and it tasted better, too. One driver of this was that Mom would occasionally bake white bread from scratch, and that'll ruin you for the store stuff; commercial whole wheat is much closer in taste and texture to scratch versions.