Folks, the industry has us a bit duped on wood mulch. Here are some thoughts seeing as we constantly get bombarded with the benefits / necessity of wood mulch:
I see no mention of GHG. Tree services often cannot find a use for the trees they cut down (which is strange because you would think they could mill it and sell the lumber). In the end, they dump trees they were paid to remove into landfills. When trees rot they release methane gas, which is 10× worse than CO₂.
I bring this up because wouldn’t wood mulch have the same problem?
I think it would have the same problem if it was in a landfill. If you have it exposed to oxygen it should decompose mechanically and aerobically and not produce as much methane.
I vaguely recall that there are good and bad ways to dump it in a landfill. You can bury it well, but the rot creates methane gas pockets just below the surface which escape into the atmosphere when dug up. When it’s rotting on the surface, it gradually leaks methane as it’s produced. Though I think it’s less rot when aired out. Mulch likely has ~½ the surface area against the soil and rotting there, so I would expect notable methane in that case.
Anyway, I’ve read nothing specific on it but conjecture that it should be studied. All that work capturing the carbon into tree wood only to cause the emission of a much worse GHG.
I see no mention of GHG. Tree services often cannot find a use for the trees they cut down (which is strange because you would think they could mill it and sell the lumber). In the end, they dump trees they were paid to remove into landfills. When trees rot they release methane gas, which is 10× worse than CO₂.
I bring this up because wouldn’t wood mulch have the same problem?
I think it would have the same problem if it was in a landfill. If you have it exposed to oxygen it should decompose mechanically and aerobically and not produce as much methane.
I vaguely recall that there are good and bad ways to dump it in a landfill. You can bury it well, but the rot creates methane gas pockets just below the surface which escape into the atmosphere when dug up. When it’s rotting on the surface, it gradually leaks methane as it’s produced. Though I think it’s less rot when aired out. Mulch likely has ~½ the surface area against the soil and rotting there, so I would expect notable methane in that case.
Anyway, I’ve read nothing specific on it but conjecture that it should be studied. All that work capturing the carbon into tree wood only to cause the emission of a much worse GHG.