Wood-ash application to forest land has been proposed as a means to compensate for increased nutrient removal at high harvest intensity. A study-plot experiment was established on a mineral soil site in Sweden to study how this measure affects soil-water chemistry. In 1995, ten treatments were applied. Here we present results from years nine to seventeen after application for eight of the treatments: control, 3×10<sup>3</sup>, 6×10<sup>3</sup> and 9×10<sup>3</sup> kg ha<sup>-1</sup> of self-hardened and crushed wood ash (WA), 150 kg N ha<sup>-1</sup> supplied as ammonium nitrate, 3×10<sup>3</sup> kg WA and 150 kg N ha-1 applied simultaneously, 3×10<sup>3</sup> kg WA with 150 kg N ha<sup>-1</sup> applied one month before the ash, and 3×10<sup>3</sup> kg ha<sup>-1</sup> of pelleted ash. Soil-water samples were collected from a depth of 50 cm. Treatment effects (<i>p</i><0.05) were detected in the electrical conductivity, pH and concentrations of K<sup>+</sup>, Mg<sup>2+</sup>, Ca<sup>2+</sup>, Al, SO<sub>4</sub><sup>2-</sup>-S and B. Elevation of K<sup>+</sup> and SO<sub>4</sub><sup>2-</sup>-S concentrations tended to cease towards the end of the study period. Effects were generally more pronounced with increasing ash dosage. No difference between the treatment 150 kg N ha<sup>-1</sup> and control was detected. Despite the high solubility of the ash, effects on the soil-water chemistry could still be detected nine to seventeen years after application.
