Managing Insect Pests 

By: Nick Seiter

Insects can reduce crop yield and quality, either by feeding directly on the marketable portion or by indirectly stressing or killing the plant. Many insects can be considered pests of alfalfa, corn, soybean, or wheat; however, only a relative few are frequently encountered at economically significant densities in Illinois. This chapter considers “key” pests, which should form the basis of insect management strategies for these crops, as well as some “occasional” pests that, while frequently encountered, rarely cause economic damage. | Learn more


Managing Diseases

By: Nathan Kleczewski and Chelsea Harbach

There are many pathogens that can cause disease in field crops grown in Illinois. However, diseases are not problematic in every field in every year. This is because several factors are required for a disease to occur. The plant disease triangle outlines the three conditions that are needed in order for disease to occur: a virulent pathogen, a susceptible host, and a conducive environment. The longer these three conditions remain together, the more disease will occur. Disease will not occur when these components are not simultaneously present. | Learn more



By: Chelsea Harbach and Nathan Kleczewski

Nematodes are roundworms, similar to the animal parasites encountered in livestock and pets. Soil-dwelling nematodes are both beneficial and harmful in crop production. The good nematodes, which don’t get much press, feed on fungi, bacteria, other nematodes, and other creatures that live in the soil and thereby recycle the nutrients contained in it. The presence of some of these types of “good” nematodes can be used as an indication of soil health. Tens of millions of mostly beneficial nematodes live in each square meter of cropland; however, a few of these microscopic roundworms—the plant-pathogenic nematodes—give all nematodes in crop production a bad name. This chapter addresses the most important plant-pathogenic nematodes in Illinois agriculture. | Learn more


Water Management 

By: Richard A. Cooke and Laura E. Christianson

A superior water management program seeks to provide an optimal balance of water and air in the soil, which allows full expression of genetic potential in plants. The differences among poor, average, and record crop yields generally can be attributed to the amount and timing of the soil’s water supply. Indeed, a large part of getting agriculture “right” involves getting the water “right.” When there is not enough water, one irrigates and when there is too much water, one can improve land drainage. | Learn more

Water Quality

By: Laura E. Christianson and George F. Czapar

Water quality can be evaluated in many ways: color, odor, temperature, turbidity, and the presence or absence of bacteria. Pharmaceuticals and personal care products have also been identified in many of the lakes, rivers, and streams in the United States. Current water quality issues in Illinois generally relate to drinking water safety and the need to reduce nutrient loss from agricultural fields. This chapter is organized around those two themes. | Learn more


Weed Management 

By: Aaron Hager

Numerous plant species are considered weeds in agronomic cropping systems. Weeds have many attributes undesirable to crop producers, not the least being the ability to reduce crop yields through competition for resources such as sunlight, water, nutrients, and space. Weeds also may harbor insects and provide a host for certain plant pathogens. Some weed species, such as wild garlic and eastern black nightshade, can reduce the quality of the harvested crop. Eliminating or reducing the deleterious effects of weeds on agronomic crops is the ultimate goal of weed management. Integrated weed management includes all practices that enhance a crop’s competitive ability and decrease weeds’ ability to reduce yield. |  Learn more