2026 Soybean Sentinel Plot Report: July 7, 2026

Again this growing season, the Pennsylvania Soybean Board is funding a Soybean Sentinel Plot Program, which is being managed by The Department of Entomology at Penn State and executed by Penn State Extension. In this effort, Penn State Extension Educators will be regularly scouting about 20 'typical' soybean fields across Pennsylvania and reporting the populations of plant pathogens and insect pests that they find. These fields will be planted with untreated soybean seeds and will not receive other applications of preventative insecticides or fungicides. Our goal is to inform the agricultural community about which pests are active across the state, so folks will have a sense of what to expect when they scout their own fields as part of an IPM program. It would be inappropriate to use these reports to justify insecticide or fungicide applications.

Data from our previous 14 years of scouting have clearly shown that most soybean fields in Pennsylvania do not develop economically damaging populations of pathogens or insect pests. All the soybean fields we have scouted harbor communities of insect pests and pathogens, but their abundance has infrequently exceeded economic thresholds, meaning that they did not need to be controlled with insecticides or fungicides. For insect pests, only three fields out of about 260 fields (over 14 years) have needed an insecticide. Growers can benefit from our results because they show that insecticides and fungicides are not necessary to grow soybean profitably, so farmers can save money by not deploying them preventively each year. A viable alternative would be to use integrated pest management (IPM) to make decisions about deploying pesticides. See our fact sheet if you would like more information on how to use IPM to manage your soybean fields.

Overview of reports from around Pennsylvania

We have five reports this week from nine fields in five counties. Their reports cover fields from growth stage V2 to R1, reflecting the diversity of soybean growing areas in PA. The reports indicate low pest populations in the soybean fields that we are scouting. As is typical for this time of year, our reports identify bean leaf beetle and Japanese beetle, but soybean aphid was found in one field. Given recent dry conditions, disease reports are low, but the most recent scouting efforts is starting to show a diversity of diseases, which are largely at low abundance. Scout your own fields to learn what is active in your area. Good luck!

Background on the project

This growing season, the Pennsylvania Soybean Promotion Board is funding a Soybean Sentinel Plot Program, which is being managed by the Department of Entomology at Penn State and executed by Penn State Extension. In this effort, Penn State Extension Educators are regularly scouting about 20 'typical' soybean fields in about 15 counties across the state, reporting the populations of plant pathogens and insect pests that they find. Our goal is to inform the agricultural community about which pests are active across the state, so folks will have a sense of what to expect when they scout their own fields as part of an IPM program. It would be inappropriate to use these reports to justify insecticide applications.

In the reports below, pests that were found during scouting are listed with their severity, which is rated on a 1–10 scale with 10 being the highest. A severity score of 1 equates to 10% or less infestation or defoliation, a "2" aligns with 20% or less infestation or defoliation, and so on. Growers should be sure to check their own fields to determine their local populations, but these reports will indicate which pests are likely to be active in fields. Our reports are distributed via this weekly newsletter.

Reports

6 July 2026 – Butler County – Stephen Campbell

Field near North Washington

Growth Stage: V3

• Bean leaf beetle – Severity: 1
• Japanese beetle – Severity: 1
• Deer – Severity: 3
• No diseases noted

6 July 2026 – Lawrence County – Stephen Campbell

Field near Fombell

Growth Stage: V2

• Bean leaf beetle – Severity: 1
• Japanese beetle – Severity: 1
• Slugs – Severity: 1
• Deer – Severity: 3
• No diseases noted

6 July 2026 – Lancaster County – Heidi Reed / Brooke Coble, Jacob Sherry

Three fields: one near Collins, one near Elizabethtown, one near Willow Street

Growth Stage: R1-R2

• Bean leaf beetle – Severity: 1
• Grasshoppers – Severity: 1
• Japanese beetle – Severity: 1
• Mexican bean beetle – Severity: 1
• Silver spotted skipper caterpillar – Severity: 1
• Soybean aphid – Severity: 1
• Deer – Severity: 1
• Alfalfa mosaic virus – Severity: 1
• Bacterial blight – Severity: 1
• Cercospora leaf blight – Severity: 1
• Downy mildew – Severity: 1
• Phyllosticta leaf spot – Severity: 1
• Septoria brown spot – Severity: 2

1 July 2026 – Indiana County – Stephen Campbell

Field near Brush Valley

Growth Stage: V3

• Bean leaf beetle – Severity: 1
• Slugs – Severity: 1
• No diseases noted

30 June 2026 – Lebanon County – Del Voight / Brooke Coble, Helen Sleat

Three fields: one near Lebanon, one near Annville, one near Bordnersville

Growth Stage: R1

• Grasshoppers – Severity: 1
• Silver-spotted skipper caterpillar – Severity: 1
• Deer – Severity: 1
• No diseases noted