Using Paper Mill Sludge and Compost in Potato Production: Firs

Introduction and Research Objectives Use of organic by-products as soil amendments in agricultural production exemplifies a strategy for converting wastes to resources. Paper mill sludge is one of the largest underutilized organic by-products in Wisconsin. Paper mill sludge (PS) generation in Wisconsin increases approximately 5% per year, and 70% of all PS generated currently (740,000 dry tons) is land filled (Wisconsin Paper Council, 1998; pers. comm.). As landfill options decline for both economic and environmental reasons, the paper industry is shifting focus to beneficial reuse (J. Katers, UWEX Solid and Hazardous Waste Educ. Ctr., 1998; pers. comm.). At present, only 12% of PS generated (88,000 dry tons) is land spread; however, there is growing interest in using PS as a soil amendment. Use of PS or PS compost in annual crop production systems holds promise from a soil quality perspective, particularly in course-textured sandy soils where increases in organic matter content can improve soil chemical, biological and physical properties.