Black Cutworm Flocks To Indiana; Scouting Proves Critical

Record numbers of black cutworm moths have descended upon Indiana fields, and after a week of warm temperatures and rainfall now is a critical time to scout, a Purdue Extension entomologist says.

Pheromone trap cooperators throughout the state monitor for the insect’s arrival, which has the potential to cause significant economic damage to field crops. A round of storms originating in southern states in March brought not only rain to Indiana, but cutworm populations not previously seen. Since that time additional captures have had the trappers very busy counting.

According to John Obermeyer, the key to successfully controlling the insect is to scout early and often and to apply insecticides when larvae are small – especially because large larvae are difficult to control.

“Producers may have a false sense of security with the seed-applied insecticides or Bt corn,” he said. “As many learned the hard way last year, these technologies don’t stand up to severe infestations, which certainly are a possibility this year.”

Infestations and black cutworm development are first determined by the moth trapping network, then by monitoring heat units once critical catches are recorded. Heat units are calculated as the difference between the average daily maximum and minimum temperatures and a critical developmental threshold temperature. For black cutworm, that threshold is 50°, meaning it takes about 300 heat units from egg hatch to the time when larvae begin to “cut” or severely damage plants.

In the southern part of the state, accumulated heat units already are well above 300 and are rapidly approaching that number in the central and northern parts. With most of the state’s corn crop already in the ground, Obermeyer said scouting now is crucial.

“Scout by inspecting 20 consecutive plants in each of five areas of a field for cutworms and feeding activity,” he said. “Be sure to check areas that had an accumulation of weedy growth before or at the time of planting.”
Obermeyer also said growers need to collect black cutworm larvae to determine the average instar, or development stage.

“A foliar, rescue insecticide may be necessary if three percent or more of the plants are damaged and black cutworm’s average larval instar is 4-6,” he said.

A larval instar guide is available inside the front cover of the Purdue Extension Corn and Soybean Field Guide, available for $7 through Purdue Extension: The Education Store here.

Pheromone trap reports and updated heat accumulation graphics are available in Purdue Extension’s Pest and Crop Newsletter here.

Leave a Reply

Insecticides Stories

Young corn plants in soil
Crop InputsFortenza Insecticide Seed Treatment Receives EPA Registration
May 25, 2017
Fortenza seed treatment insecticide from Syngenta has received registration approval from the U.S. EPA for use on corn and cotton Read More
Soybean aphid leaf
InsecticidesMulti-state Research Reveals IPM Best Option for Treatment of Soybean Aphids
May 17, 2017
About 89.5 million acres of soybeans will be planted across the U.S. in 2017 — a record high, according to Read More
Lygus pratensis
Crop InputsCalifornia Agriculture: What A Difference A Year Makes For Insect And Disease Control
April 3, 2017
“We finally got the rain,” David Haviland, Entomology and Pest Management Farm Advisor with the University of California Cooperative Extension, Read More
Golden Harvest Corn healthy leaves
Crop InputsFMC Emerges as DuPont Crop Protection Business Buyer, Becomes 5th Largest Ag Chemical Company
March 31, 2017
FMC Corp. and DuPont today announced the signing of a definitive agreement for FMC to acquire the portion of DuPont’s Read More
Trending Articles
Migrant farm workers
LegislationTrump: Immigration Crackdown Won’t Impact U.S. Agriculture
May 16, 2017
President Donald Trump said he would seek to keep his tough immigration enforcement policies from harming the U.S. farm industry Read More
AGCO Ratliff featured
Eric SfiligojRemembering Robert Ratliff
May 15, 2017
With all the fast-paced happenings in agriculture this spring, with multiple mergers in the works and planting season in full Read More
Case sprayer nozzle closeup
EquipmentSpray Application: A Nozzle Renaissance
May 2, 2017
If you had asked four-decade ag veteran Mark Bartel, President of Wilger Inc., just a few years ago what lay Read More
ManagementWashington Update, Dow-DuPont Earnings, and the Passing of an AGCO Legend
April 27, 2017
Editors Paul Schrimpf and Eric Sfiligoj talk about the latest Beltway news, crop protection company 1st quarter numbers, and the Read More
Crop InputsFlying Under the Radar No More, FMC Goes Big
April 13, 2017
Describing FMC as “under the radar,” admittedly, is probably a stretch. But in a snap of the fingers, FMC upped Read More
Young Corn Plants
Crop NutritionStill Hunting Yields
April 1, 2017
There’s no denying it — the agricultural marketplace today is undergoing a fundamental shift in fortunes. Not too many years Read More
Latest News
ManagementTrip Report, PSM R.I.P, and Ag’s Reaction to Federal Bu…
May 25, 2017
Editors Paul Schrimpf and Eric Sfiligoj talk about their recent travels, the end for Process Safety Management (PSM), and how Read More
Corn soil
LegislationARA Member Testifies Before Senate Ag Committee
May 25, 2017
Agricultural retailers stand on the front-lines of the American economy. As trusted advisors to America’s farmers, ag retailers are uniquely Read More
Young corn plants in soil
Crop InputsFortenza Insecticide Seed Treatment Receives EPA Regist…
May 25, 2017
Fortenza seed treatment insecticide from Syngenta has received registration approval from the U.S. EPA for use on corn and cotton Read More
ManagementFarm Market iD’s Agriculture Database Now Covers More T…
May 25, 2017
Farm Market iD, farmmarketid.com, has announced the release of its 2017 Annual Update of its farm and land database. The Read More
Food IT Fork-to-Farm
Precision AgThe Mixing Bowl Event Connects Technology, Food, and Ag…
May 24, 2017
For the fourth consecutive year, The Mixing Bowl presents FOOD IT, under the theme “Fork to Farm.” Action-oriented entrepreneurs, industry Read More
Photo credit: The United Soybean Board/The Soybean Checkoff.
Seed/BiotechKansas State University Researchers Find New Pathogens …
May 24, 2017
A single seed seems so simple. Put it in the ground, give it some care, and you’ve soon grown food. Read More
Soybean Field
HerbicidesNew Dicamba Herbicide Premix Coming Soon from Syngenta
May 24, 2017
Syngenta has announced the name of its new herbicide featuring the active ingredients of S-metolachlor and dicamba. Upon registration by Read More
Eric SfiligojMonsanto ‘Picks Its Battles’ by Nixing Deere Deal
May 23, 2017
Having been in the trade journalism game since the mid-1980s, I remember several watershed moments during my career. One of Read More
FungicidesSyngenta Launches New Seed Treatment Fungicide
May 22, 2017
Syngenta has announced the launch of PLENARIS seed treatment fungicide for the control of downy mildew in sunflower. PLENARIS contains Read More
Corn close up
Crop InputsMonsanto’s First HPPD Herbicide Garners EPA Appro…
May 19, 2017
Monsanto announced today that EPA has federally approved Harness MAX Herbicide, the first herbicide in the Monsanto portfolio to provide Read More
ManagementPrecision Planting Deal, China Developments, and Enviro…
May 18, 2017
Editors Eric Sfiligoj and Dan Jacobs discuss the latest news on John Deere’s now dead deal for Precision Planting, China’s Read More
Soybean aphid leaf
InsecticidesMulti-state Research Reveals IPM Best Option for Treatm…
May 17, 2017
About 89.5 million acres of soybeans will be planted across the U.S. in 2017 — a record high, according to Read More
GROWMARK-2017-Interns
CropLife 100GROWMARK Names 2017 Summer Interns
May 16, 2017
Forty-two college students are exploring agricultural career opportunities this summer as GROWMARK interns. They are working at FS member cooperatives Read More
Migrant farm workers
LegislationTrump: Immigration Crackdown Won’t Impact U.S. Ag…
May 16, 2017
President Donald Trump said he would seek to keep his tough immigration enforcement policies from harming the U.S. farm industry Read More
Flooded corn in Indiana
FertilizerBoth Wet and Dry Conditions Threaten Nitrogen Loss
May 15, 2017
The weather is notoriously unpredictable, leading to challenges for planting, harvesting and applying the nitrogen (N) your corn crop needs. Read More
farmer Kip Tom
Precision AgAg Tech: On the Cusp of Something Big?
May 15, 2017
The investment and ag-tech sectors’ continuing courtship of agriculture, smoldering for three or four years now, was well in evidence at Read More
AGCO Ratliff featured
Eric SfiligojRemembering Robert Ratliff
May 15, 2017
With all the fast-paced happenings in agriculture this spring, with multiple mergers in the works and planting season in full Read More
Greg Musson, Gar Tootelian
ManagementOpinion: Shaking Your Perspective in Ag Retail
May 12, 2017
Some of you I’m sure have encountered our recently retired salesman extraordinaire, Dan Bellanger. He worked in the industry for Read More