Weather Conducive To Wheat Head Scab, Corn Armyworms

Last week, wheat fields in Barton County were scouted by Wyatt Miller, an agronomy assistant with University of Missouri Extension.

“The majority of wheat scouted this week was in the flowering stage. Some fields have just begun to flower, while in others, flowering is complete,” said Miller.

Miller says producers should be scouting their fields to determine if pesticide applications may be warranted. Current weather conditions have slowed the growth of wheat and may be conducive for head scab if wet weather continues.

Wheat is most susceptible to head scab at flowering. Head scab is favored by temperature range of 77-86° F, frequent rains, overcast days, and high humidity.

“Head scab is treated by using a preventative measure of a fungicide application. Producers should consider yield potential, future weather, and growth stage when considering fungicide application,” said Miller. “Once flowering is completed, head scab treatment will not be justified. If fungal diseases reach the leaf just below the flag leaf, fungicide application may still be appropriate.”

Wheat producers should also be scouting for true armyworms. True armyworm populations have been light in wheat this spring, but a few fields have required an insecticide application.

According to MU Entomologist, Wayne Bailey, economic thresholds are met when an average of four or more half-grown or larger worms per square foot are present during late spring and before more than 2 to 3% of seed heads are cut from stems.

“Although foliage feeding always occurs with true armyworm larvae, cutting of wheat heads from plants occurs only in some years,” said Miller. “No head cutting has been reported, but wheat should be monitored several times per week after heading as true armyworm larvae can cut most heads from plants in a two to three day period once they begin cutting heads.”

Very small larvae are pale green in color, but quickly change to yellowish-brown or tan bodies with tan to brown heads mottled with darker brown patterns. Three distinct broad, longitudinal dark stripes run the length of the body with one occurring on the back and one running down each side. Also one or more orange lines can be found running the length of each side of the body from head to tail.

To determine the presence of small larvae, scout plant debris on the ground and for feeding damage on lower plant foliage. Small larvae are best scouted during late afternoon, evening , and early morning hours. As larvae increase in size, they will feed during both night and day periods and move upward on host plants as they consume foliage.

Corn producers should be scouting fields for black cutworms and true armyworms. Black cutworm moths typically begin arriving in Missouri from southern states about April 1 with peak flights occurring about April 10 annually.

“While the risk of economic infestations in field corn is now reduced, it is still possible for moth flights to continue for several weeks and cause problems in corn,” said Miller.

The economic threshold for black cutworm in field corn is to treat when three-fourths of an inch or smaller larvae cause two to three percent or more of seedling plants to wilt or be cut above or below ground up to the 5-leaf stage of corn seedling growth.

“Black cutworm damage was seen in fields scouted this week and was reported to be above economic threshold levels in some fields in the area. True armyworm treatment in seedling corn is justified when 25% or more of plants are being damaged. True armyworm damage has not been seen yet in wheat or corn.”

Leave a Reply

Fungicides Stories

Retailer Wheat
Crop InputsGrowers Looking For Selectivity, Flexibility With Fungicide Options
February 5, 2017
Selectivity remains the name of the game in 2017. “People that were more selective last year and didn’t get burned Read More
Young Corn Closeup
FungicidesArysta LifeScience Receives EPA Approval On New In-Furrow Products
February 2, 2017
Arysta LifeScience North America recently received EPA approval on two new products, both of which feature patented formulation technology that Read More
FungicidesSudden Death Syndrome In Soybeans Can Often Go Overlooked
January 26, 2017
Because the symptoms of SDS appear similar to many other soybean diseases, SDS can be easily overlooked, according to Damon Read More
Soilborne disease in soybean Martin Chilvers
FungicidesSoilborne Diseases Impact Soybeans
January 26, 2017
2016 was quite a year! Unfortunately for some it was an especially damaging year to their soybean crop from soilborne Read More
Trending Articles
Farmer and aptop
Matt Hopkins10 Warning Signs Your Website Is Grossly Outdated
February 8, 2017
Your Website is often a visitor’s first impression of your ag retail business. A positive first impression can set the Read More
AgriSync
Matt Hopkins17 Agriculture Apps That Will Help You Farm Smarter In 2017
December 9, 2016
Ag professionals are working smarter, not harder, than ever before. Smart farming technologies have enabled them to reduce costs, maximize Read More
R4023 Sprayer, John Deere
CropLife 100Ag Retail Equipment Report: The Green Party Continues
December 7, 2016
In the annual race for sales in the ag retail equipment marketplace, the color schemes for participants are a little Read More
Mike Stern
Precision AgClimate Corp. CEO Talks Retailer Support For Digital Ag
December 1, 2016
CropLife Magazine’s sister publication, AgriBusiness Global, recently sat down with Mike Stern, CEO of The Climate Corp., following the Monsanto subsidiary’s Read More
Precision AgTrimble Debuts End-to-End FMIS Platform
November 28, 2016
October’s inaugural PrecisionAg Vision Conference left this author with many thoughts and things to ponder in the coming months. Probably Read More
CHS Primeland
CropLife 100The 2016 CropLife 100 Report: Reviewing The Many Bulls And Bears Impacting This Year’s Marketplace
November 28, 2016
For virtually all of 2016, the nation was wholly focused on the big Presidential election. Some folks aligned themselves with Read More
Latest News
SprayersApache 1000 Series Sprayer Earns 2017 EquipmentWatch Hi…
February 21, 2017
ET Works has been named a winner in the 2017 EquipmentWatch Highest Retained Value Awards program, the industry’s only award Read More
Measuring Bulk Tanks
StewardshipMeister Media Among 2017 Award Winners Presented By The…
February 21, 2017
The Pesticide Stewardship Alliance (TPSA) held its annual conference in San Diego, CA, earlier this month where three awards were Read More
John Reifsteck
CropLife 100GROWMARK’s Reifsteck Earns NCFC Director Of The Y…
February 21, 2017
GROWMARK Chairman of the Board and President John Reifsteck has earned the prestigious Director of the Year Award from the Read More
Roy Blunt
LegislationARA Recognizes Blunt, Heitkamp For Legislative Efforts …
February 17, 2017
Agricultural industry continues to face federal regulatory challenges. Thankfully, agriculture’s allies in the U.S. Senate stepped forward. The Agricultural Retailers Read More
LegislationThe Fertilizer Institute Commends Senate On Confirmatio…
February 17, 2017
The Fertilizer Institute (TFI) President Chris Jahn issued the following statement on the Senate confirmation of Oklahoma Attorney General Scott Read More
Trump, Senate, Cabinet
LegislationBREAKING: Trump EPA Nominee Scott Pruitt Confirmed by S…
February 17, 2017
Scott Pruitt, who as Oklahoma’s attorney general spent years suing the Environmental Protection Agency over its efforts to regulate various Read More
ManagementFebruary Road Trip Edition
February 17, 2017
Editors Paul Schrimpf and Eric Sfiligoj discuss their recent visits to Indiana and Kentucky. Read More
Heritage Cooperative Finished Building Aerial
ManagementHeritage Cooperative, Agland Co-op Approve Merger
February 17, 2017
Agland Co-op and Heritage Cooperative stockholders have both approved the merger agreement between Agland Co-op and Heritage Cooperative. Now begins Read More
LegislationARA Fly-In: Ag Retail Descends on Capitol Hill, Lawmake…
February 15, 2017
More than 100 agricultural retailers, distributors and suppliers headed to Capitol Hill Tuesday morning for the Agribusiness Congressional Fly-in, according to a Read More
Untreated soybean seed Heartland Coop
Seed/BiotechMarrone Bio Innovations, Groundwork BioAg Bio-stacked M…
February 13, 2017
Marrone Bio Innovations, Inc. and Groundwork BioAg, Ltd have announced successful seed treatment field trials of the world’s first all-biological Read More
NL5000 With G5 Technology
SpreadersNew Leader Introduces NL5000 Dry Nutrient Applicator Wi…
February 13, 2017
New Leader, a division of Highway Equipment Company (HECO), has announced the next generation of spreading technology with the NL5000 Read More
Fertilizer Storage
Crop InputsThe State Of The Fertilizer Industry
February 9, 2017
He’s all hat, no horse.” It’s a humorous way of describing a person who tells a good story, but is Read More
CropLife 100Pinnacle Agriculture Agrees To Credit Agreement Amendme…
February 9, 2017
Pinnacle Operating Corp. has entered into an amendment (the “Amendment”) to its First Lien Credit Agreement that will provide for, Read More
ManagementUpdates on Upcoming Trips, Dow-DuPont, and the Des Moin…
February 9, 2017
Editors Paul Schrimpf and Eric Sfiligoj review a few future travels, along with the latest on big company mergers and Read More
Championship Tractor Pull
EquipmentNational Farm Machinery Show Highlighted By Championshi…
February 9, 2017
The scream of monster engines, the stench of burning rubber and the ground-pounding vibrations of the country’s largest, loudest and Read More
Farmer and aptop
Matt Hopkins10 Warning Signs Your Website Is Grossly Outdated
February 8, 2017
Your Website is often a visitor’s first impression of your ag retail business. A positive first impression can set the Read More
Corn Field
InsecticidesArysta LifeScience, DuPont Collaborate On Rynaxpyr Prem…
February 8, 2017
Arysta LifeScience recently announced that it has entered into a global collaboration with DuPont Crop Protection for the development of Read More
Industry NewsThe Fertilizer Institute Board Elects New Chairman, Vic…
February 8, 2017
The Fertilizer Institute’s (TFI) Board of Directors has elected Chuck Magro, President and CEO of Agrium, and Tony Will, President Read More