re meadow area of that year, corresponding to 10% of the total mire area. In 1880, the area of mire meadows used by farmers in Abborrtjärn had grown to 60 ha, or 22% of the total mire area (Figure 3).
When the productivity of mire meadows and unused mires was compared, as graded in 1880, we found that mire meadows had grades from 1 (=best grade) to 50 (median 11.5), whereas unused mires had grades from 8 to 100 (median 50) (Figures 4 and 5). There were thus both considerable differences and considerable overlap between used and unused mires. Meadows with good grades represented very small areas, whereas most unused mires were considered to be of low value and covered much larger areas. When the mire-meadow area peaked in the late 1800s, all of the best-grade and most medium-grade mires were being routinely harvested (Figure 4).
When we compared the rankings of the 25 mire meadows that were classified in both 1805 and 1880, four meadows had risen 10 positions or more, suggesting that some measures had been taken to enhance their productivity. In only one case, however, do we have a record of this, namely Klockarmoren, which went from the second-lowest position in 1805 to the absolute top in 1880. Although nothing is said in the official documentation, local tradition has it that Klockarmoren was illegally reclaimed in the early 1800s by a farmer from a neighboring village (Anon., 2015), and today it is arable land. Assuming active human intervention, such as fertilization, as the cause of the increased productivity of all four abovementioned meadows, the area affected would be around 4.5 ha, or less than 2% of the total mire area.
We found no traces of catchwork irrigation systems in the study area, but we identified two cases where the mire meadow area had been increased through artificial flooding. The records from the timber floating association state that two dams existed in 1864, when timber floating was just beginning. Both of these dams were located at the outlet of lakes surrounded by mire meadows, Bergtjärnen and Renbergstjärnen. A comparison of the maps from 1805 and 1880 shows that the meadow area increased from 0.3 to 7.9 ha around Bergtjärnen and from 0.3 to 4.7 ha around Renbergstjärnen. The map from 1805 does not contain any data on unused mires, so we do not know whether the increased meadow areas were gained from forest or from mire. If we assume the latter, the conclusion would be that about 12 ha of mires, or 4%, were converted into meadows through artificial flooding. Later, damming was mainly adapted to the needs of timber floating. The dam at Renbergstjärnen was abandoned in 1935 and the one at Bergtjärnen in 1967, when timber floating ceased (Archives of Umeå flottningsförening).
As previously mentioned, the mire meadow Klockarmoren is said to have been illegally reclaimed already in the early 1800s (Anon., 2015). It eventually became arable land, and is one of the very few former mire meadows that is currently cultivated. There is a central ditch through the field, and possibly also covered ditches. However, we do not know what measures were taken to reclaim the area during the 1800s; it was still classified as a mire meadow in 1880, with irregular shape, and does not appear in any official documentation on ditching projects. Another early reclamation project was connected to a new settlement, Koverberget, which was established in 1886 on land belonging to Abborrtjärn village, but which is now abandoned (Larsson, 1988). The DTM reveals that there are ditches, probably dug around that time, along the former fields of the settlement, and most of these ditches concern areas that were in 1880 classified as ‘mire’. This small-scale, private initiative was followed around 1900 by a large state-financed project to prevent frost damage in Abborrtjärn and several neighboring villages (Väg- och vattenbyggnadsstyrelsen, 1872–1910). The cadastral map from 1912 shows a large central ditch through Vorrmyran (Figure 2d), which was probably a result of that project. In 1915, another ditching plan was established f