Northern peatlands store ~500 Pg C and are important ecosystems for global climate regulation. Wildfire is the largest natural disturbance to peatlands within the Boreal Plains of western Canada. Historically, low severity fires in this region release less carbon than accumulates over a fire return interval (~120 years), allowing peatlands to maintain their carbon sink function. While peat combustion (measured as depth of burn) is typically low ranging, from 5-10 cm, during prolonged drought, or in drained peatlands, peat burn severity can reach depths >1 m, threatening the carbon sink function of boreal peatlands. Peatland drainage disturbs the ecohydrological feedbacks that maintain a peatland’s resilience to fire. The lowering of the water table results in lower near surface moisture conditions, increased above ground fuel loading and canopy cover, and shifts in surficial vegetation communities, all of which increase vulnerability to deep peat combustion. Utilizing pristine and drained portions of a peatland complex which burned during a wildfire in 2021, we examine how afforestation processes and other landscape factors, such as peat depth, distance to drainage ditch, and proximity to upland hummocks, control the occurrence of deep peat smouldering. We show that distance to ditch, pre-fire peat depth, and above ground fuel loading exhibit strong controls on peat burn severity, and that drained peatland margins (close to adjacent uplands) experience the greatest peat burn severity. Identifying potential smouldering hotspots by utilizing easy to measure landscape characteristics can aid in highlighting areas that should be prioritized for proactive management and restoration.