Late Planting: 10 Key Insects To Watch

Questions are surfacing about the impact of late planting on key insect pests of corn and soybeans, said Mike Gray, University of Illinois Extension entomologist. Based upon the progress of planting this spring, Gray said he can understand the interest.

Here are 10 key corn and soybean insects growers and retailers should keep a close eye on this spring:

1. Western corn rootworms. Western corn rootworm larvae typically begin to hatch during Memorial Day weekend celebrations. Above-normal temperatures for the remainder of May could accelerate this time line, Gray said. In general, late planting tends to reduce the likelihood of economic infestations of corn rootworms.

“During the past few days (May 7 to 11), corn planting has been progressing at a very impressive clip across many areas of the state,” he said. “At this point, unless corn planting is set back again due to a prolonged stretch of wet weather, I don’t believe the slow pace of planting will affect western corn rootworm densities this growing season.”

2. Black cutworms. Fields that have been tilled and planted late this spring are more susceptible to black cutworm injury. Corn is at most risk when planted into fields that have supported dense populations of winter annual weeds. Gray said he has seen many fields that match this description this spring.

“Don’t be lulled into complacency just because a Bt hybrid has been planted,” he warned. “Large infestations of black cutworms (anticipated this spring) can potentially overwhelm certain Bt hybrids. I urge producers to look for early signs of leaf feeding to assess the potential threat of cutting.”

3. European corn borers. Although few growers worry about this pest anymore, Gray said early planting tends to favor the establishment of the first generation. Late planting increases potential problems with the second generation.

4. Bean leaf beetles. Bean leaf beetle establishment is affected by many factors, including their ability to overwinter as adults beneath plant debris in wooded or sheltered areas, Gray said. Although many areas in Illinois experienced very cold temperatures this past winter, snowfall was abundant and likely provided a blanket of insulation.

“As bean leaf beetles break their dormancy and begin emerging from their overwintering sites, they often first fly to alfalfa fields,” he said. “Early-planted soybean fields are most at risk to early-season bean leaf beetle feeding. Because soybean planting will be later this season, I don’t anticipate large economic infestations of this insect this spring. Any early-planted and isolated field of soybeans located near a wooded area is always at risk to bean leaf beetle injury.”

5. Soybean aphids. Soybean aphid densities were very low throughout Illinois in 2010. In fact, suction trap counts in September and October of last year were exceptionally low, Gray said. These sub-economic adult densities led to very few eggs on its overwintering host, buckthorn.

“I anticipate a very weak flight of aphids to soybean fields this spring,” he said. “The late planting of soybeans will further contribute to a downward spiral of aphid densities early in the season. If the summer of 2011 is mild, aphid densities could certainly rebound by late season. The reproductive power of this insect is impressive. A hot summer may result in another “no-show” for this insect.”

6-7. White grubs and wireworms. In general, delays in corn planting negatively affect densities of these soil insect pests. If planting has occurred and seedlings are subjected to prolonged periods of cool and wet soil conditions, increased levels of root injury by white grubs and feeding on below-ground portions of the stem may occur by wireworms.

“As soil temperatures increase, wireworm larvae typically begin to move deeper into the soil profile and away from the seed zone”, Gray said. “Corn that is planted later in the month into soils that are becoming progressively warmer may not experience as much wireworm injury.”

Annual white grubs, such as Japanese beetle grubs, typically complete pupation by late May and early June. Consequently, their potential to injure late-planted corn is greatly diminished the further planting is delayed in May. However, true white grubs have a three-year life cycle and may injure corn root systems all summer long the second year of their life cycle. Accurate identification of grub species is key to their effective management, Gray said.

8-10. Corn earworms, corn leaf aphids, and fall armyworms. Many insects migrate into the Midwest each year. However, it’s a bit too early to determine how the planting may affect densities of corn earworms, corn leaf aphids, and fall armyworms, Gray said.

“Corn may reach the pollination period at a later date in July this season, typically a period of the summer more prone to hot and dry conditions,” he said. “These insects may reach economic densities on corn plants growing under more stressful conditions this year. Time will tell.”

(Source: Illinois Ag Connection)

Leave a Reply

Insecticides Stories

Corn Field
InsecticidesArysta LifeScience, DuPont Collaborate On Rynaxpyr Premix Formulations
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
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
Scott Stewart, University of Tennessee
InsecticidesInsecticides: How To Win With A Smaller Arsenal
January 24, 2017
There’s no way around it: Loss is a central theme this year in dealing with insect pressure in the U.S. Read More
Soil Young Corn
InsecticidesAtticus Launches New Acetamiprid Alternative
January 3, 2017
Atticus recently announced the introduction of a line of products containing the active ingredient Acetamiprid, an insecticide that works quickly 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
Greenleaf Technologies TADF03-D Dual Fan Nozzle
NozzlesSix Greenleaf Nozzles Approved For XtendiMax With Vapor…
February 22, 2017
Greenleaf Technologies has announced that six of its TurboDrop D Series nozzles have been approved for use with Monsanto’s XtendiMax Read More
Winter Wheat
Industry NewsTiger-Sul Hires Manitoba And Eastern Canada Account Man…
February 22, 2017
Tiger-Sul, a global leader in sulphur fertilizers and crop performance products, has announced that sales veteran Trevor Loewen has joined Read More
NFMS 17 Hagie Sprayer
Eric SfiligojThe Read From Louisville: Uncertain
February 22, 2017
By the time this column appears across the country, the annual Commodity Classic will be in full swing. This means Read More
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