Braathen Dendrokronologiska Undersökningar
Lunnevägen 2, SE-46144 Trollhättan, Sweden
Gerum church, Gotland
Gerum (Sv.K. 219) church about 40 km S of Visby. The church has chancel with apse, which is older than the nave. The portal embraces are sculptured with plant-shaped ornaments.
A tie-beam from the chancel bonding the truss of the apse has squared cross-section (sample no 3). Its outermost annual ring is dated 1156. As the piece lacks waney edge the dating gives no information because we do not know how many rings which have been removed from the original log. By studying characteristic parts of the building it can be settled that the chancel with apse does not belong to the early period of erection of stone churches on Gotland.
A moulding board (sample no 16) in the relieving arch of the nave, east, has waney edge and is dated 1299. Experience shows that moulding boards may be somewhat earlier than timber from the truss. The boards may have been used already when working on the lower parts of the church. If one wants to estimate the time when the nave has been ready made there should be added one or a few years, which in this case means that we have reached into the first years of the 14th century. When the nave was completed may be of interest in connection with studying mural paintings, but the shape of the building and the stone works probably were decided in the planning period.
The belfry lacks datable medieval timber.