Like most things in the modern world, an accurate answer is nuanced.

The most sustainable way to farm would be to open pastured cattle, pigs, and sheep which would drop manure in a fallow field and add tons of organic nutrients to the soil - as happens in nature. That pasture would then be used to grow crops the next year, as the animals are rotated to another area. When an area is only used for growing vegetables, there is a net depletion of natural nutrients that have to be supplemented with external input.

The worst part of agriculture is farming ONLY beef or ONLY dairy or ONLY vegetables on acreage. I'm going to risk being contrarian to the HN crowd - but farming can't be automated in a sustainable way. The ecosystem is far too multivariate and interrelated. Sure, you can make a smarter tractor, but that land will be barren in 40 more years. Automation only works at scale, but nature does not divide into neat discrete categories without some sort of tradeoff in biodiversity or long-term resilience

In Montana, that sort of agriculture would quickly destroy the soil.

It only takes a few passes with a plow to turn it into desert, so pretty much the only way of getting calories from land in Montana is by grazing cattle or bison.

Kind of irrelevant though, ranch land in Montana only support a few cattle per square mile.

I'm a big proponent of no-till farming. There are some interesting experiments with intensive small-scale farming with introducing compost and mulch to more or less barren areas, which provide enough nutrition to grow 'compost crops' which can supplement the soil further. It might be an interesting place to try carbon-recapture projects and build a microclimate.

I don't know enough about Montana, but I'm mostly worried about what monoculture farms are doing to the fertility of the Midwest.

Zero-till is awesome. Most of the farmers in Saskatchewan aren't quite fully zero-till but till a lot less than they used to. But zero-till is not organic, so the masses think it's bad.

> thrive on land you can’t actually use for any other sort of farming.

True. Unfortunately the majority of meat does not come from grass fed animals.

Doesn't matter from a CO2 point of view. Sheep are better than cattle in this regard, but you still have to transport sheep, feed them crops in the winter, and so on. The net CO2 cost is still high. You're better off from an efficiency point of view in using that energy to grow more vegetables. We could probably grow forests for the carbon capture on most Welsh hillsides where sheep are grazed.