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During rain-free periods, the water table in peatlands falls and the moisture content ( MC) of top 10 cm, including the moss layer, depends upon the hydrophysical properties and the responses of the local composition of species to water deficit. Thus, the ecosystem becomes vulnerable to surface peat fires. The spread of such fires is often irregular; however, there is little understanding of how the fine-scale variation of peat MC can affect the spread of smouldering fire. We analyse the fine-scale distribution of surface MC from a degraded blanket bog (i.e., horizontal intervals of 10 cm), thus indirectly analysing the effect of fine-scale MC distribution on peat fire spread. We determine the relationship of vegetation and microtopography to the spatial distribution of near surface MC and the moisture gradient around patches of dry peat (less than 250% MC, moisture content in a dry mass basis). We found that the MC of the surface peat was distributed in clusters with dry patches (less than 250% MC) averaging 40 ± 15 cm in size. The MC gradient surrounding dry patches was 10 ± 7% MC∙cm−1. A mixed-effects model showed that dry patches were associated with lawns (of feather moss or Sphagnum) and hummocks of feather moss. Our model showed that wet patches were associated with both hummocks and hollows of Sphagnum. Therefore, the characterization of the surface MC in a fine-scale is critical if we are to understand the spread of fires in peatlands. [ABSTRACT FROM AUTHOR]