The subject of cow flatulence and methane causes me to wonder what happens to the carbon in the grass that grows and dies naturally. When grass rots, how much of the carbon is converted to soil thus trapping the carbon, and how much carbon is released as CO2 or methane? I assume that this depends on whether the rotting process involves aerobic or anaerobic bacteria, but is there any way to guess at typical numbers? I realize that deforestation goes hand in hand with the issue of cattle in many areas, but it seems to me that cows are otherwise getting a bad rap. Since grass grows to replace the grass that has been eaten, thus absorbing as a minimum the equivalent in carbon release by the cow, isn't a free-range cow carbon neutral at worst? Edit: I should say cow burps - eructation. It seems that the flatulence bit is also a little unfair to our friends of the bovine persuasion.