Our aim in this study was to evaluate whether coverage change in the vegetation of a forestry buffer wetland can be used to reveal a possible increase in nutrients. To achieve this, we followed changes in vegetation on two peatland buffers, and biomass with nitrogen content in one of them. Nutrient concentrations were periodically lower in the water inflow than in the outflow. Flooding caused a species change in favor of flood-tolerant grasses and Sphagna, but this species composition did not indicate a higher trophic level. Nitrogen content in the reference site's original surface peat layer, which was rich in woody remains, was higher than that of the newly formed, more acidic Sphagnum peat of the spruce swamp buffer. Changes in biomass did not indicate an increased nutrient-binding capacity of the spruce swamp buffer vegetation. On the other hand, the changes in species cover outlined the area of effective water flow paths within the buffer and suggested that severe eutrophication of peatland forestry buffers does not seem likely.