Reading a paper about using roots to measure forest fire carbon releases:
The paper mentions forest fires that burn under a tree burn 6.4% less deep into soil organic layer than where there is no tree. There is more carbon in deeper layers. Still, at 10kg of carbon/m^2, only including stores in the first foot or so, this suggests a few cms of moss or litter is enough to keep sequestered maybe 300g/m^2 of carbon in a forest fire. Under the trees is less litter and where there are no trees is 3cm of litter. If the paper is right, a few cms of litter or moss that contain only dozens of grams of carbon/m^2 would preserve perhaps 10x as much carbon in the soil beneath, during a forest fire. The paper only mentions a fraction of 3cm difference sequestering 6.4% of soil carbon depth, but even more litter/moss ougth to yield even greater soil carbon sequestration if/when a forest fire happens.
Sphagnum fuscum will take 3-30 years to become 3cm of "brown moss", depedning on BM definition. A faster growing plant would yield the protective behaviour quickly. Brachythecium (a moss) grows 6 vertical inches/yr. Cat-tails spread up to 17 horizontal inches/yr. If either of these when decomposed to peat and survivors removed as weeds, form a useful peat substrate for Sphagnum fuscum, such labour intensive land management would be cost-effective in a carbon-priced world over a large area.