The moss layer varies from patchy to continuous, and generally includes Hylocomium splendens and Pleurozium schreberi. Sphagnum species may occur on wetter sites. Other understory components are similar to those found in white spruce stands and black spruce stands. Mixed forests form where paper birch codominates in stands with black spruce and white spruce, and where white spruce codominates in stands with balsam poplar. Low scrub bogs are characterized by open, low mixed shrubs and tussock-forming sedges.
Woody plants are scarce.
Wet forb herbaceous marshes are characterized by an open cover of wetland emergent species. Aquatic mosses often are present. Wildfire Occurrence of wildfire in the Interior Bottomlands Ecoregion is very common. A high occurrence of lightning storms, warm and dry summer climate, and stands of vegetation with branches low to the ground aid the ignition and spread of wildfire. Fire season generally lasts from June through the beginning of August.