August is often overlooked in terms of its agronomic importance. April, May, June and July are active planting, fertilizing and pest management times. September, October and November are spent harvesting, planting and fertilizing. Granted, we all need a recharge period, especially following a hectic field season and before shifting into harvest mode.

However, August can be an extremely important month for protecting a promising crop, preparing for future crops, reviewing crop status, documenting crop health and incorporating that information into an efficient agronomic management program.

MFA agronomists are commonly called to visit fields after harvest to determine what factors influenced the season's crop production. I often refer to these visits as "forensic agronomics." August is a much better time than post harvest to evaluate variables that influenced crop growth and yield.

It is now too late to apply most weed control products, with the exception of some late-planted soybeans and certain perennial or forage-based weeds that are better controlled through fall management. However, August is an excellent time to evaluate the effectiveness of the 2002 weed control program. It is late enough to document most germination flushes and any early established weeds that escaped crop protection treatment. It is also early enough to estimate weed density and weed species diversity.

August scouting provides final identification of which weeds were major problems. You need to document where in the field these weed infestations occurred. This can be done through traditional documentation or through more sophisticated GPS/GIS-based scouting, mapping and record keeping programs. The bottom line is to document what weeds are present, where they were and what level of infestation.

August crop evaluation is a complement to and not a replacement for more proactive field scouting programs conducted earlier, when more effective in-season weed control measures can be conducted.

Many crop insect issues can be monitored in August. Northern corn rootworm, grasshoppers, fall armyworm, corn earworm, European corn borer and Southwestern corn borer are all active August corn insects.

Even if you don't treat for these insects, other management practices may be justified. An example would be prioritizing field harvest schedules based upon corn borer activity to help prevent yield losses caused by plant lodging.

When walking cornfields in August, look for silk clipping, ear feeding, premature eardrop, stalk breakage and goose necking. August is a good month to evaluate the success of programs like Bt corn and to plan for insect-related residue and crop rotation best management practices.

Common late-season soybean insect pests in the lower Midwest include: armyworms, bean leaf beetle, spider mites, stinkbugs and grasshoppers. We rarely need to treat for these soybean insects, but when they occur in large numbers, yields are drastically reduced.

Corn diseases commonly observed in August include: gray leaf spot, rust, northern/southern corn leaf blight, crazy top (especially this year with heavy spring rainfall), smut, and several stalk and ear rots. Knowing which diseases are present can help determine harvest management (may need modified to address lodging, mycotoxins, etc.). Knowing which late-season diseases are present will also aid in crop rotation and variety selection for future crops.

Soybean diseases commonly observed in August include: charcoal rot, septoria brown spot, frogeye leaf spot, soybean mosaic virus, soybean cyst nematode, phytophthora root and stem rot, rhizoctonia root rot, fusarium root rot, sudden death syndrome, white mold, brown stem rot, phomopsis seed decay/pod and stem blight, cercospora/purple seed stain and stem canker.

Identifying if these diseases exist will help make future soybean management decisions for your fields. Many of these diseases are seed borne, and if present will affect the quality and usability of seed produced from infected seed production fields.

In addition to the corn and soybeans discussed above, cotton, rice, milo, alfalfa and other forage crops need August evaluation. Cotton and rice production cultures generally have a well-defined crop evaluation system in place. Forages generally receive less evaluation, a philosophy that needs changing. August is an excellent time to evaluate forage stand, species diversity, species density, potential yield and overall sward health. By doing so, you can help develop long-term forage system management planning.

The bottom line is that August is an important agronomic information collection month. It is an excellent time to evaluate the 2002 crop and use that information when planning future agronomy activities. MFA has a network of certified crop advisers and agronomists to help address your late-season crop production needs and how they relate to future crop production practices. Please do not hesitate to use this resource.