"Potash Production in Northern Sweden: History and Ecological Effects of a Pre-industrial Forest Exploitation"

Östlund, L., O. Zackrisson, and H. Strotz. “Potash Production in Northern Sweden: History and Ecological Effects of a Pre-industrial Forest Exploitation.” Environment and History 4, no. 3 (Oct., 1998): 345–358. doi:10.3197/096734098779555592. Potash (potassium carbonate; K₂CO₃) was one of the most important industrial chemicals in Europe prior to the 20th century. It was obtained from wood-ash from broadleaved trees, which was refined in several steps into the pure chemical. The production primarily took place in the periphery of Europe, in Russia and in the United states. In Sweden, potash was produced in the southern parts on a larger scale from the 17th century. In northern Sweden the production started in the early 19th century, reached considerable proportions within a few decades, and then ceased completely in the 1860s. The trees used were primarily birches (Betula pubescens and B. pendula). Previous research on the subject of Swedish potash production has concluded that the production ceased due to shortage of raw material. Through studies of historical records and experimental potash production, the authors challenge these conclusions. They assert that potash production in northern Sweden lost out to German producers, who started to produce potash industrially at the same time that production in northern Sweden ceased. The ecological significance of the potash production is difficult to estimate, primarily because the impact caused by this form of forest exploitation is obscured by subsequent logging and other human activities. Nevertheless, the removal of large old broadleaved trees was one important step in the large-scale transformation of the forest landscape which has influenced the structure and function of north Swedish forest ecosystems. All rights reserved. © 1998 The White Horse Press