Data from undrained boreal pine mires and a drainage-age sequence of drained sites

Vegetation and soil property data from 84 sites representing undrained and drained boreal pine mires. These are peatland sites with a peat layer at least 1 m thick that have been at least sparsely forested in their natural state. The tree stands were composed of Scots pine (Pinus sylvestris; dominant tree species at all sites), with varying proportions of pubescent birch (Betula pubescens) and Norway spruce (Picea abies) at the nutrient-rich part of the site type gradient. The drained sites had been ditched between 1933-1984 to increase tree growth. All drained sites represented the first tree stand generation following drainage, i.e., trees already present before drainage as well as trees that had emerged through natural regeneration following drainage. Sampling and measurements were done during 1987-1992. Separate data sheets for general site information, soil chemical characteristics, soil water retention capacity, tree stand composition, litter layer composition, peat plant remain composition, and ground vegetation composition. Other data in Excel xlsx format; ground vegetation data in txt files formatted for ordination analyses (the same data in two different formats). The original Finnish-language site information sheets are also available as pdf files. The data have been used in several publications that are listed as references and where sampling and measurements are described.