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.

The Problem Defined
The Central Sands is Wisconsin's foremost vegetable producing region. It is characterized by intensive, irrigated crop production on sandy soils underlain by increasingly contaminated aquifers. Vegetable producers currently are faced with declining crop prices, higher input costs, and increasing pressures to reduce pesticide and commercial fertilizer use. Mounting concern about environmental contamination from vegetable production in the Central Sands has spurred interest in alternative crop management systems. The Wisconsin Potato Vegetable Grower's Association (WPVGA) has proposed soil quality improvement as one of their central goals in sustaining vegetable production while minimizing negative environmental impacts.

Central Wisconsin is also home to large-scale paper production, which produces paper mill sludge as an organic by-product. For example, the Consolidated Paper Company in Wisconsin Rapids produces approximately 46,000 wet tons of PS annually. While much of their PS is land spread on cropland as Consogro™, other paper mills in the region largely rely on landfills for disposal.

Project goals and benefits
There is growing interest in using PS in vegetable crop production in the Central Sands. However, many vegetable processing plants will not accept crops grown with PS because of concern about crop contamination with organic chemical residues and trace metals. If we can quantify the short and long term soil and crop benefits associated with PS use and allay concerns about potential vegetable contamination, perhaps both vegetable producers and processors will
recognize its value and promote more widespread land use. Previous evaluations of PS use in crop production have focused on short-term improvements in soil fertility like nutrient availability and crop yield. Paper mill sludge amendments should also improve soil properties like bulk density, water holding capacity, aggregate stability and cation exchange capacity.

Full description of project
Potatoes and papermill residuals powerpoint presentation