Ballastplasser og ballastplanter i Telemark

Bjørndalen, J. E. & Ouren, T., 1975. Ballast heaps and ballast plants in the country of Telemark in Norway. Norsk geogr. Tidsskr. 29, 55–68.

At the peak time of the sailing ship trade in the latter half of the nineteenth century, ballast was brought to Telemark partly from vessels loading ice, partly from vessels brought to the numerous shipyards for careening and repair. Some ballast was also brought to the properties of the shipowners resident in the area. The fate of some of the alien plants, which were introduced with ballast into Telemark, was investigated. Most were casuals, which disappeared when the ballast traffic ceased at the time of the First World War. Others may still be found close to some of the old ballast heaps and a few have managed to extend their area. English summary.