Field Guides Allow Quick, In-field Diagnosis of Soybean Problems

May 21, 2009
ICM News

By Tamsyn Jones, Corn and Soybean Initiative

Corn and soybean planting is almost done. As young plants start to emerge, growers will increasingly want to watch for pest and disease issues that could affect yield. An Iowa State University Extension field guide series is available to help farmers, agronomists and crop advisors quickly diagnose plant problems.

The Iowa Soybean Association partnered with ISU Extension to produce the guides in 2008.Copies are available free from the ISU Extension online store.

field guides

The series currently includes three pocket-sized, weather-resistant guides covering management of general soybean pests and diseases, soybean cyst nematodes and soybean aphids. A companion tri-fold pamphlet on speed-scouting of soybean aphids, which includes step-by-step directions and a worksheet for individual field assessment, is also available. The series provides the latest research and information on managing yield-lowering soybean pests and diseases. Photos accompany descriptions of all pests and diseases.

The Soybean Disease & Pest Management Field Guide covers a variety of leaf, seed and root diseases; damage from environmental stresses; and the primary insect pests that target soybean plants. It also explains soybean growth stages, planting considerations in Iowa and integrated pest management.

The Soybean Aphid Management Field Guide focuses on the soybean aphid, a major pest first found in Iowa in 2000. Since its arrival, several major outbreaks occurring in alternating years have caused significant yield loss. The guide explains the soybean aphid life cycle, identification, virus transmission, injury symptoms, management considerations, natural aphid enemies and treatment options. It also gives background on the origin and history of soybean aphids in Iowa, thoughts on population variation and insecticide considerations.

The Soybean Cyst Nematode Management Field Guide covers the life cycle, biology and management of soybean cyst nematodes, the most destructive soybean pest in the United States. The guide explains how nematodes damage soybean plants, symptoms of damage, scouting and soil sampling techniques, long-term management options, nematode effects on other soybean diseases and when to consider a nematode type test.

Portability and ease of use in the field were key goals in designing the guides. The spiral-bound books are visual aids with succinct text and a sturdy build that can resist mud, rain and other realities growers face working their fields.

While some of the information in the guides is specific to Iowa growing conditions, people outside the state may still find it useful and relevant. Those outside Iowa who use the guides should check with their state Extension services for local recommendations.

To obtain the guides visit the online store at and search by category or reference number.The soybean pest and disease guide is CSI 0010; the aphid guide is CSI 0011; the cyst nematode guide is CSI 0012; and the aphid speed scouting companion pamphlet is CSI 0015.


Tamsyn Jones is a communications specialist with the Corn and Soybean Initiative. Jones can be reached at (515)294-7192 or email at

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on May 21, 2009. The information contained within may not be the most current and accurate depending on when it is accessed.