Soybean Sentinel Plot Program September 11, 2018

With soybean maturity approaching in most fields, insects and diseases are becoming less relevant, but most pest populations remain low.
Soybean Sentinel Plot Program September 11, 2018 - News

Updated: September 12, 2018

Soybean Sentinel Plot Program September 11, 2018

Brown marmorated stink bugs on soybeans in Clinton County. Most soybean fields in Pennsylvania are in growth stage R6 or later and so are past the point when insects, like stink bugs, or diseases will reduce yield. Image Credit: Greg Roth

Our reports this week from 8 counties across Pennsylvania continue to indicate that populations of insects and pathogens are low. Most fields have reached growth stage R6 or later, so insect feeding and disease infestations are unlikely to reduce yield.

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 25 or so ‘typical’ soybean fields in twenty counties across the state, reporting the populations of plant pathogens and insect pests that they find. Our goal is to inform folks which pests are active across the state, so that they 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”).

Scouting Reports

11 September – Bradford County – Casey Guindon

Growth stage: R6

  • Japanese beetle – Severity: 1
  • Slugs – Severity: 1
  • Frogeye leaf spot – Severity: 1
  • Septoria brown spot – Severity: 2
  • White mold – Severity: 1

11 September – Crawford County – Joel Hunter

Growth stage: R6

  • Japanese beetle – Severity: 1
  • Green stink bug – Severity: 1
  • Mexican bean beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Septoria brown spot – Severity: 1

10 September – McKean County – Nicole Carutis

Two fields
Growth stage: R5

  • Japanese beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Lady beetles abundant
  • Frogeye leaf spot – Severity: 1
  • Septoria brown spot – Severity: 1

10 September – Potter County – Nicole Carutis

Two fields
Growth stage: R5

  • Grasshoppers – Severity: 1
  • Japanese beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Lady beetles abundant
  • White mold – Severity: 1
  • Frogeye leaf spot – Severity: 1
  • Septoria brown spot – Severity: 1
  • Soybean downy mildew – Severity: 1

7 September – Centre County – Adriana Murillo-Williams

Growth stage: R6

  • Brown Marmorated Stink Bug – Severity: 1
  • Grasshoppers – Severity: 1
  • Japanese beetles – Severity: 2
  • Soybean aphid – Severity: 3
  • Silver-spotted skipper caterpillar – Severity: 1
  • Lady beetles abundant
  • Alfalfa Mosaic Virus – Severity: 1
  • Frogeye leaf spot – Severity: 1
  • Soybean Downy Mildew – Severity: 1
  • Soybean Sudden Death Syndrome – Severity: 1

7 September – Mercer County – Claire Coombs

Growth stage: R7

  • Grasshoppers – Severity: 1
  • Frogeye leaf spot – Severity: 1
  • Septoria brown spot – Severity: 1
  • Soybean Sudden Death Syndrome – Severity: 1

6 September – Union County – Anna Busch

Growth stage: R6

  • Bean leaf beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Silver-spotted skipper caterpillar – Severity: 1
  • Brown marmorated stink bug – Severity: 1
  • Lady beetles abundant
  • Soybean downy mildew – Severity: 1
  • Septoria brown spot – Severity: 1

6 September – Northumberland County – Anna Busch

Growth stage: R7

  • Silver-spotted skipper caterpillar – Severity: 1
  • Grasshoppers – Severity: 2
  • Lady beetles abundant
  • Soybean mosaic virus – Severity: 1
  • Frogeye leaf spot – Severity: 1

Authors

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

More by John Tooker, Ph.D.