> because whatever get burned had once collected the carbon from the air. (Not an expert, just guessing here) That is a long-term part of it. Specifically, bi

> because whatever get burned had once collected the carbon from the air. (Not an expert, just guessing here) That is a long-term part of it. Specifically, biomass is a lot better than fossil fuels because you are not introducing any more carbon into the long-term cycle. But it is not all about the amount of 'above ground' carbon. In the short term, what matters more is 'carbon in the atmosphere'. Here, biomass is net-zero only if either the plants being burned are re-planted (i.e. wood pellets) or the biomass would have rotted away anyway (food remains). On the other hand, cows take up a lot of acreage that could be used to capture a lot more carbon if the fields weren't filled with just grass. Besides, the actual practice of keeping cows is quite resource intensive. And, as others have said, cows produce methane.