Soybean Sentinel Plot Program Report for September 12, 2017

This week pest pressures continue to be low for our maturing soybeans in the R6-7 stages. Insect damage has negligible effects on yield after the R5 stage.
Soybean Sentinel Plot Program Report for September 12, 2017 - News

Updated: December 7, 2017

Soybean Sentinel Plot Program Report for September 12, 2017

Reports this week from across Pennsylvania continue to indicate low pest populations in the soybean fields we are scouting. Most of our fields are in the mid-reproductive stage (R6-7) and a lot of insect damage becomes inconsequential after R5, so keep this in mind. Our reports from this week identify Japanese beetles, and grasshoppers as the primary defoliators, but aphids and brown marmorated stink bugs are present in some fields. For diseases, reports of Septoria brown spot and frogeye leaf spot are present in some fields, but pest pressure remains low.

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. 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 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.

Reports

9/8 – Armstrong, near Dayton – Rachel Milliron*

Growth Stage: R6

  • Frog-3
  • Septoria-3
  • BLB-3
  • Japanese Beetle-3
  • Grasshoppers-1
  • Green stinkbugs

9/8 – Blair, near Martinsburg – Zachary Larson

Growth Stage: R6

  • Japanese beetle – 1
  • Bean leaf beetle - 1
  • Grasshoppers - 2
  • Green stinkbug – 1
  • Frogeye leaf spot – 1
  • Cercospora leaf blight - 1
  • Brown spot - 1

9/8 – Cambria, near Loretto – Zachary Larson

Growth Stage: R6

  • Bean leaf beetle – 1
  • Bacterial blight – 1
  • Frogeye leaf spot – 2
  • Brown spot – 1

9/11 – Columbia – Joel Imgrund

Growth Stage: R7

  • Grasshoppers - 3
  • Downy Mildew - 1
  • Frog-eye -2

9/12 – Crawford – Joel Hunter

Growth Stage: R6

  • Septoria glycines (brown spot) 1- slight
  • Still grass hoppers, leafhoppers, and bean leaf beetle … all 1- slight.

9/10 – Elk, near Kersey – Mellissa Strong

Growth Stage: R6

  • Sunscald - severity: 1
  • Brown spot- Severity: 1
  • Bacterial leaf blight - severity: 1
  • Green Stink Bug - severity: .5
  • Bean leaf beetle - severity: .5
  • Japense Beetle - severity .5
  • Lady beetles - present

9/6 – Franklin, near Greencastle – Kelly Patches

Growth Stage: R6

  • - Bean leaf beetle: 1
  • - Potato leafhopper: 1

9/10 – Jefferson, near Brockway – Mellissa Strong

Growth Stage: R5.5

  • Downy mildew - severity: 1
  • Frogeye leaf spot - severity: .5
  • Bean leaf beetle - severity: 1
  • Green Stink Bug - severity: 1
  • Soybean aphid- severity 1

9/11 – Northumberland – Joel Imgrund

Growth Stage: R7

  • Grasshoppers - 2
  • Downy Mildew - 1
  • Frog-eye -1

9/11 – Union – Joel Imgrund

Growth Stage: R7

  • Grasshoppers - 4
  • Downy Mildew - 1
  • Frog-eye -1

12-Sep – York, near east Stewartstown – John Rowehl

Growth Stage: R6

Damage level 2 Insect Pests found:

  • Grasshoppers

Diseases:

  • Sudden death
  • Brown spot
  • downy mildew

12-Sep – York, near south Stewartstown – John Rowehl

Growth Stage: R6

Damage 2 Insect Pests found:

  • grass hoppers
  • Japanese Beetles
  • Bean Leaf Beetle
  • Mexican Bean Beetles
  • Green Stink Bug
  • Brown marmorated stink bug
  • Green Clover Worms
  • Silver spotted skippers

Diseases:

  • brown spot
  • downy mildew

12-Sep – York, near Windsor – John Rowehl

Growth Stage: R6

Damage level 1 Insect Pests found:

  • Silver Spotted Skippers
  • Grasshoppers

Diseases:

  • brown spot
  • Stem canker
  • brown stem rot and/or Phytopthora stem rot

Authors

Insect ecology Plant-insect interactions Conservation biological control Chemical ecology Gall insects

More by John Tooker, Ph.D.