Black spruce swamps are characterized by their strongly acidic peat soils, canopy dominated by black spruce and tamarack, and near-continuous layer of Sphagnum mosses. They are similar to northern tamarack swamps, which are also dominated by tamarack, but tamarack swamps tend to be more minerotrophic, often have a more discontinuous layer of Sphagnum, and have a higher prevalence of tall shrubs, usually at least 5% cover, and often up to 25% cover or more. Black spruce swamps often grade into muskegs, which are differentiated by having stunted trees with a lower canopy cover (generally 10-25%). They also often co-occur with and grade into open bogs and poor fens, which are distinguished by having even more stunted, sparser trees (generally less than 10% canopy).
