Long-term Tillage and Crop Rotation Effects on Soil Carbon and Soil Productivity

Tillage system and crop rotation have a significant, long-term effect on soil productivity and soil quality components such as soil carbon and other soil physical, biological, and chemical properties. In addition, both tillage and crop rotation have effects on weed and soil disease control. There is a definite need for well-defined, long-term tillage and crop rotation studies across the different soils and climate conditions in the state. The objective of this study was to evaluate the long-term effects of different tillage systems and crop rotations on soil productivity

Biochar and Managed Perennial Ecosystems

Biochar is a carbon-rich material that is similar to charcoal. It is produced when biomass is burned in the absence of oxygen, a process otherwise known as pyrolysis. Pyrolysis and the production of biochar are currently being promoted as a means to both produce domestic fuel (bio-oil) while concurrently producing a co-product that increases crop yield and sequesters carbon in the soil (biochar). While there may be many potential benefits in the application of biochar to agricultural soils, such as enhanced soil fertility and improved soil water status, there are no studies of higher-order ecological and ecosystem effects of biochar and its potential synergistic interactions (either positive or negative) on complex perennial systems. The goal of this field experiment is to determine how biochar and manure addition directly affect ecosystem structure and function in perennial systems, specifically soil nutrients, water, plants, and soil organisms.

Yields of Corn, Soybeans, and Alfalfa in Western Iowa: 1990 to 2011

The ISU Western Research Farm, Castana, Iowa is one of the oldest in Iowa dating to 1946. It also has a unique location in the loess hills of western Iowa. The research farm was set up to study the deep loess soils, particularly crop production and soil conservation methods. Although the work at the research farm has transitioned away from traditional plot work, yields of major crops grown at the farm, and climate data are collected each year. Crop yields are a reflection of current technologies and weather. In western Iowa, rainfall is especially critical and is often the limiting factor.