It is one of the largest high peat bogs in the Janowskie Forest with thickness up to 6 metres. The reserve is dominated by high peat bog vegetation, with a significant share of transitory bogs and water plants and rushes. The bog is surrounded by forest vegetation, made of bog forest, moist forest and fresh forests. The reserve includes 45 plant communities. The communities include 139 species of macrofungi, 71 lichen species, 82 species of moss and about 500 species of vascular plants, including as many as 27 species of protected species.