Properly managed landfill is given a cover to prevent gas release, and gas harvested via wells. https://en.wikipedia.org/wiki/Landfill_gas https://en.wikipedia.

Properly managed landfill is given a cover to prevent gas release, and gas harvested via wells. https://en.wikipedia.org/wiki/Landfill_gas https://en.wikipedia.org/wiki/Landfill_gas Anaerobic decay of carboniferous matter produces much less carbon loss as gas than aerobic decay. Captured methane is destructively utilised, reducing its greenhouse gas concerns. Processing fibre crops into particular bioplastics can also reduce potential for gaseous decay. This seems favourable when compared to trees which produce large quantities of openly decaying matter (e.g. fallen leaves) throughout their lives, and unless lumbered, will almost entirely decay when they die.