Soybeans in Centre County are hosting very low insect pest and disease populations (Photo by Adriana Murillo-Williams, Penn State Extension)

Summary of reports from around Pennsylvania:

The reports this week continue to reveal small insect pest populations and almost no diseases. Bean leaf beetle and grasshopper nymphs, which are typical for this time year, were reported from most sites, but populations are low and not concerning. Soybean aphids and silver-spotted skipper caterpillars were also found, but again populations are low. All these populations of pest species should be tracked but in our fields they are nowhere near threatening yield. Remember that soybean fields can provide great habitat for natural enemies, and the attractiveness of fields increases as rows canopy over. Natural enemies that colonize fields early in the growing season are responsible for keeping most fields free of economically damaging pest populations for the rest of the season. It is therefore wise to avoid unnecessary insecticide applications to not disrupt your allies in pest control.

For diseases, Septoria brown spot was found in a few fields, but populations were low. Scout your own fields to learn what is active in your area. Good luck!

Background

This growing season the Pennsylvania Soybean Promotion Board is funding a Soybean Sentinel Plot Program, which is being managed by The Dept. of Entomology at Penn State and executed by Penn State Extension. In this effort, Penn State Extension Educators are regularly scouting about 25 'typical' soybean fields in about 20 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 your local populations, but these reports will indicate which pests are likely to be active in fields. Our reports are distributed via this weekly newsletter and are available via the Penn State Extension website (then search for "soybean sentinel plot").

Reports

28 June 2022 – Montgomery County – Andrew Frankenfield

Near Souderton

Growth stage: V1

• No insects or diseases of note

28 June 2022 – Potter County – Nicole Santangelo / Jack Thomas

One field near Ulysses

Growth stage: V4

• Septoria brown spot – Severity: 1
• No insects of note
• Deer damage present

27 June 2022 – Adams County – Heidi Reed

Near Littlestown

Growth stage: R2

• Japanese beetle – Severity: 1
• Grasshopper – Severity: 1
• No other insects or diseases of note

27 June 2022 – Beaver County – Justin Brackenrich / Adam Hohn

Near Fombell

Growth stage: V3

• Grasshopper – Severity: 1

• No insect pests or diseases of note
• Deer damage present

27 June 2022 – Bedford County – Leanna Dupptstadt

Field near Fishertown

Growth stage: V2

• No insect pests or diseases of note
• Beneficial arthropods present: spiders

25 June 2022 – Lancaster County – Jeff Graybill

Field between near Manheim

Growth stage: R1

• Bean leaf beetle – Severity: 1
• Septoria brown spot – Severity: 1

24 June 2022 – Centre County – Adriana Murillo-Williams

Field between Bellefonte and State College

Growth stage: V5

• Bean leaf beetle – Severity: 1

• Grasshopper – Severity: 1
• Silver-spotted skipper – Severity: 1
• Soybean aphid – Severity: 1
• Soybean leafminer – Severity: 1