This study involved a dendrochronological examination of oak (Qeurcus.sp) and Scots pine (Pinus.sylvestris) in the nationalpark Blå Jungfrun, by measuring annual ringwidth data from tree-cores from the island, data from the national forest inventory and climatedata from the Swedish Meteorological and Hydrological Institute (SMHI). Using the analysis program Windendro an annual ringwidth analysis was performed. Trends that occured were that pine respondend more to precipitation than temperature and that oak respondend more to temperature. Ringwidth were higher for Scots pine than oak and for both species lower than on the mainland.