Soybean Sentinel Plot Report for July 31, 2018

Even with the extremely wet weather, our soybean scouting is finding minor insect/disease populations. The soybeans, and all of us, could all use a little sun.
Soybean Sentinel Plot Report for July 31, 2018 - News

Updated: August 1, 2018

Soybean Sentinel Plot Report for July 31, 2018

Scouting soybeans under clear skies, a rarity recently. Image Credit: Jennifer Bratthauer

Summary of reports:

Our reports this week from 12 counties across Pennsylvania counties indicate that populations of insects and pathogens continue to be low in Pennsylvania soybean fields. With the wet weather, the threat from grasshoppers and spider mites has declined greatly. In some fields, Japanese beetle and Septoria brown spot populations appear to be building, but even these populations mostly appear to be below economically damaging levels. Scout your fields to determine the local populations. At the predominant levels, it is unlikely that insecticides or fungicides will be profitable, but exceptions are always possible.

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.

31 July 2018 - Lancaster County - Jeff Graybill

Growth Stage – R4

  • Japanese beetle – Severity: 2
  • Green cloverworm – Severity: 1
  • Bean Leaf Beetle – Severity: 1
  • Septoria Brown Spot – Severity: 1

31 July 2018 – Lebanon County – Del Voight

Four fields, all with similar populations

Growth stage: R2-R4

  • Japanese beetle – Severity: 2
  • Grasshoppers – Severity: 1
  • Green cloverworm – Severity: 1
  • Bean leaf beetle – Severity: 1
  • Septoria Brown Spot – Severity: 1

31 July 2018 – Westmoreland County – Rachel Milliron

Growth stage: R3

  • Japanese beetle – Severity: 2
  • Grasshoppers – Severity: 1
  • Septoria Brown Spot – Severity: 2

30 July 2018 – Armstrong County – Rachel Milliron

Growth stage: R3

  • Japanese beetle – Severity: 2
  • Septoria Brown Spot – Severity: 1

30 July 2018 – Bradford County – Casey Guindon

Growth stage: R3

  • Japanese beetle – Severity: 1
  • Grasshoppers – Severity: 1
  • Green cloverworm – Severity: 1
  • Lady beetles and bees abundant
  • Septoria Brown Spot – Severity: 1

30 July 2018 – Northumberland County – Anna Busch

Growth stage: R5

  • Japanese beetle – Severity: 2
  • Grasshoppers – Severity: 1
  • Green cloverworm – Severity: 1
  • Bean leaf beetle – Severity: 2
  • Potato leafhopper present
  • Soybean vein necrosis virus present

30 July 2018 – Union County – Anna Busch

Growth stage: R2

  • Japanese beetle – Severity: 1
  • Green cloverworm – Severity: 1
  • Soybean aphid – Severity: 1
  • Potato leafhopper present
  • Honey bees, minute pirate bugs, lady beetles present
  • Septoria Brown Spot – Severity: 1

30 July 2018 – Crawford County – Joel Hunter

Growth stage: R2

  • Japanese beetle – Severity: 1
  • Grasshoppers – Severity: 1
  • Bean leaf beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Septoria Brown Spot – Severity: 1

30 July 2018 – McKean County – Nicole Carutis

Growth stage: V10

  • No insect damage noted
  • Septoria Brown Spot – Severity: 4

29 July 2018 – Potter County – Nicole Carutis

Two fields

Growth stage: R1 – R3

  • Japanese beetle – Severity: 3
  • Septoria Brown Spot – Severity: 2

28 July 2018 – Butler County – Justin Brackenrich

Growth stage: R1-R3

  • Japanese beetle – Severity: 2
  • Bean leaf beetle – Severity: 1
  • Soybean aphid – Severity: 1
  • Lady beetles present
  • Septoria Brown Spot – Severity: 1

26 July 2018 – Centre County – Adriana Murillo-Williams

Growth stage: R1

  • Japanese beetle – Severity: 3
  • Green cloverworm – Severity: 1
  • Grasshoppers – Severity: 1
  • Soybean aphid – Severity: 3
  • Lady beetles abundant
  • Soybean downy mildew – Severity: 4
  • Frog-eye leaf spot – Severity: 1
  • Alfalfa mosaic virus – Severity: 4

Authors

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

More by John Tooker, Ph.D.