2005 Year in Review

From the Fields

As the 2005 growing season approaches, it’s time to plan the implementation of a crop monitoring or scouting program. The concern over Asian soybean rust will no doubt result in more individuals monitoring fields. Scouting is one of the fundamentals to a successful integrated pest management (IPM) program and it is key for the observation of field crop conditions and pest management.

As noted in the Field Crop Scouting Manual, published by the University of Illinois, field scouting determines which pests are present, what stage of growth each pest and the crop are in, whether the pests are parasitized or diseased, whether a pest population is increasing or decreasing, and the condition of the crop. All this information is used to make a decision about whether a control measure is needed.

A scouting program requires accurately written records of the field location, current field conditions, history of past pest problems and pesticide use, and a map locating present pest infestations. These records will allow the grower to keep track of each field and anticipate or diagnose unusual crop conditions.

Field crop insect pests can be monitored in several ways. Insect counts are commonly expressed as numbers per plant, per foot of row, per sweep (of a sweep net), or per unit area (square foot, etc.). Estimated crop damage is usually expressed as a percentage.

During scouting, plants should also be examined for symptoms and signs of disease. The severity of the disease is expressed on a specific leaf, or the whole plant, or the whole field depending upon the crop. Plant roots should also be examined by the crop scout. Soil samples, and at times root tissue, are needed for estimating densities of nematodes.

Early season weed scouting should be conducted within two weeks after crop emergence to evaluate the performance of herbicides and to determine if other weed control strategies may be needed. A weed map should be made for each field to show the location of various species of weeds. Over time these maps may reveal a shift in the composition of weed species within specific locations of a field.

Plant and soil samples should be taken from representative areas of the field. Sampling should be evenly distributed over the field and plants should be sampled randomly unless certain field characteristics suggest an uneven distribution of pests. One should avoid border rows and field edges unless there are specific reasons for scouting these areas. Fields should be scouted once a week, although more frequent monitoring may be needed if pest populations begin to increase rapidly.

Extension offices can assist individuals in obtaining a copy of the 280-page Field Crop Scouting Manual, written by eight University of Illinois Extension specialists.

by  Editor, theCity1.com
February 17, 2005