Cows don't need grain. Grain feeding is part of industrial meat production that is highly detrimental to the environment. Feeding cows grass (and rotating them) though has the total opposite effect. It creates soil that can hold more water and sequester carbon. So it eliminates the need for grain production because cows simply eat grass while naturally fertilizing it.

Huge fan of a carbon tax.

No way anyone can feed cows on grass alone if you want to earn big bucks or feed 200M their daily beef steak.

Do you have data comparing profits from CAFOs vs grass-fed operations? Wouldn't grass fed sellers earn more as it's a premium product?

How did the North American plains support millions of bison just on grass at one point?

Bison are easier on the grass than cows.

One problem is of course that few places are good enough carbon sinks to make grass fed beef even close to co2 neutral.

A better idea would be less regular manure and more humanure.

The other purpose beeing green fuels? Im okay with this.