Soybean Sentinel Plot Update

Posted: July 6, 2016

Grasshoppers, Japanese Beetles and Aphids are showing up now but pressure from diseases appears low thus far.

Current report: Our reports continue to indicate very mild insect pressure. Grasshoppers are the main pests that our scouts encountered in the last week, though Japanese beetles are becoming more common. We have yet to find soybean aphids in our plots but have heard one report from NY State that aphids are colonizing fields up there—we will watch our fields for them in the coming weeks. Still very little disease has been reported. We expect these results to represent the majority of soybean fields in PA, but scout your fields to find out for yourself.

The Pennsylvania Soybean Promotion Board is funding a Soybean Sentinel Plot Program, which is being managed by Penn State Extension and The Dept. of Entomology at Penn State. In this effort, Penn State Extension Educators are regularly scouting 25 or so ‘typical’ soybean fields in nineteen counties across the state, reporting the populations of plant pathogens and insect pests that they find. Our goal is to keep folks aware of pests so that they will then scout their fields as part of an IPM program. It would be imprudent to use these reports as the basis or justification for an insecticide application or including insecticides in with a post emergence herbicide application.

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. Growers should be sure to check their own fields to determine your local populations, but these reports will give you a sense of what pests are active in fields. Our reports are distributed via this weekly newsletter, Penn State’s Field Crop News, and will be available in the next day or two on Penn State’s Field Crop Entomology website.

5 July – Bradford County

Mark Madden / Mason Tate
Near Ulster
Growth stage: V4-V5

  • Very few insect pests present
  • No diseases noted

5 July 2016 – Mercer County

Gary Micsky
Growth stage: R1

  • Very slight slug feeding
  • Less than 5% defoliation across field

5 July 2016 – Crawford County

Joel Hunter
Growth stage: V4

  • Very slight slug feeding – Severity 1
  • No diseases

5 July 2016 – Erie County

Joel Hunter
Growth stage: V3

  • Very slight slug feeding – Severity: 1
  • No Disease

4 July – Potter County

Nicole Carutis/Heather Supplee
No-till, planted 30-in rows
Growth Stage: V3

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

4 July – McKean County

Nicole Carutis/Heather Supplee
Disked, Planted, 15 inch rows, 2nd year beans
Growth Stage: V4

  • Grasshopper nymphs – Severity: 1
  • Green cloverworm – Severity: 1
  • Mexican bean beetle – Severity: 1
  • Bacterial Leaf Wilt – Severity: 1
  • Septoria Leaf Spot – Severity: 1
  • Frogeye Leaf Spot – Severity: 1

1 July – Dauphin County

Liz Bosak
Four fields
Growth stage: V1-R1

  • Grasshoppers – Severity: 1
  • Japanese beetles – Severity: 1
  • No diseases noted

30 June – Perry County

Liz Bosak
Four fields
Growth stage: V4-V5

  • Grasshoppers – Severity: 1
  • Japanese beetles – Severity: 1
  • No diseases noted

30 June – York County

John Rowehl
Growth stage: V6-R1

  • Mexican bean beetle present – Severity: 1
  • Grasshoppers – Severity: 1
  • Japanese beetles – Severity: 1
  • No diseases noted

28 June – Lancaster and Lebanon Counties

Allyson Balmer / Del Voight / Jeff Graybill
11 fields, including treated and untreated seeds
Growth stages: V5-R2

  • Bean leaf beetle feeding – severity: 1-2
  • No diseases noted<

Contact Information

John Tooker
  • Extension Specialist
Phone: 814-865-7082