Pigweed Update: 4 Tips For Curtailing Palmer Amaranth Movement

The known distribution of Palmer amaranth in Illinois based on 2012–2013 surveys by university weed scientists.
The known distribution of Palmer amaranth in Illinois based on 2012–2013 surveys by university weed scientists.

Palmer amaranth (Amaranthus palmeri) has garnered much attention recently in both academic discussions and popular press releases, and with good reason. Among the weedy species of Amaranthus, Palmer amaranth has the fastest growth rate and is the most competitive with the crops common to Midwest agronomic cropping systems. Soybean yield losses approaching 80% and corn yield losses exceeding 90% have been reported in the peer-reviewed scientific literature, reports the University of Illinois-Extension’s Aaron Hager.

Palmer amaranth can be effectively managed in Illinois agronomic crops, but the greatest likelihood for successful management is with systems that employ multiple effective management tactics. Palmer amaranth is perhaps the personification of a weed species that requires an integrated management approach.

Unlike waterhemp, Palmer amaranth is not indigenous to Illinois. Palmer amaranth evolved as a desert-dwelling species in the southwestern United States, including areas of the Sonoran Desert. However, genotypic and phenotypic adaptability have allowed Palmer amaranth to expand its distribution and colonize the vastly different agricultural landscapes across much of the eastern half of the United States. The presence of Palmer amaranth in agricultural landscapes of the eastern United States is perceived by some to be only a recent phenomenon, but Dr. Jonathan Sauer, noted expert of Amaranthus taxonomy, noted in 1957 that, “It looks as if there has been recent and substantial northeastward expansion of A. palmeri resulting in its present wide area of cohabitation with interior species,” (Sauer 1957).

Will Palmer amaranth populations, likely introduced by seeds moved into Illinois from areas where Palmer amaranth has become the dominant pigweed species, be able to adapt to the landscape and growing conditions of Illinois? Perhaps a more important question is to define the damage niche of Palmer amaranth populations in Illinois agronomic cropping systems.

Recent research conducted in Illinois by Dr. Adam Davis, USDA-ARS plant ecologist at the University of Illinois, has examined these important questions. Results from these experiments have demonstrated that there are few landscape-level barriers to the establishment of Palmer amaranth populations in Illinois, and that these populations, once established, are competitive with crop species. In other words, these results indicate that it’s not a question of if Palmer amaranth will become established in Illinois, but rather when and where it will become established.

Similar to female waterhemp plants, female Palmer amaranth plants produce an abundance of seeds. These small black seeds are easily moved within and between fields in myriad ways, including harvesting and tillage equipment. If you identify Palmer amaranth in one or more fields, what can you do this fall to limit movement of the seed?

The following four suggestions were developed by weed scientists in Illinois to help curtail the movement of Palmer amaranth seed:

  1. Fields with Palmer amaranth populations should be the last fields harvested this fall and the last fields planted next spring.
  2. Mark or flag areas where Palmer amaranth plants have produced seed. These areas should be intensively scouted the following season and an aggressive Palmer amaranth management plan implemented to prevent future seed production.
  3. Do not mechanically harvest mature Palmer amaranth plants with crop harvesting equipment. Physically remove the plants immediately prior to harvest and either leave the plants in the field or place in a sturdy garden bag and remove the plants from the field. Bury or burn the bags in a burn barrel as soon as possible.
  4. Fields in which Palmer amaranth seeds were produced should NOT be tilled during the fall or following spring. Leaving the seeds near the soil surface increases the opportunities for seed predation by various granivores.

It’s not too early to begin planning an integrated Palmer amaranth management program. An integrated herbicide program should include soil-residual herbicides applied at full recommended use rates within two weeks of planting and followed by postemergence herbicides applied before Palmer amaranth plants exceed 3 inches tall. Most herbicides that control waterhemp also control Palmer amaranth, but successful, long-term management of Palmer amaranth in Illinois will likely require more than herbicides.

SOURCE: Aaron Hager, University Of Illinois-Extension, The Bulletin

Topics:

Leave a Reply

Crop Inputs Stories

Monsanto sign
Crop InputsMonsanto Speaks on Dicamba Issues in Arkansas
June 26, 2017
Monsanto’s Chief Technology Officer, Robb Fraley, issued the following statement following the Arkansas State Plant Board’s proposal to ban dicamba, Read More
Corn Field
Seed/BiotechCorn Insect Bt Technologies Offer Cost-effective, Proactive Protection
June 26, 2017
When farm economics are challenging, farmers look for ways to bolster profit margins, including reducing input costs. Some may think Read More
Crop InputsArkansas Plant Board Votes to Ban Dicamba — Now What?
June 23, 2017
The Arkansas State Plant Board has voted to pass a proposed emergency rule to ban the use of in-crop dicamba, Read More
Engenia soybeans
Crop InputsBASF: ‘Closely Monitoring’ Dicamba Situation in Arkansas
June 22, 2017
BASF, whose Engenia herbicide is the target of more than 200 drift complaints in Arkansas, emailed the following statement to Read More
Trending Articles
PrecisionAg Vision Conference
Precision AgPrecisionAg® Vision Conference: Focused on the Future
June 13, 2017
PrecisionAg® is pleased to announce the return of its PrecisionAg Vision Conference, October 10-12, 2017. Based on overwhelmingly positive response Read More
Redbanded-stinkbug-on-soybean-Photo-credit-Thomas-County-Ag
Crop InputsExperts: Mild Winter, Early Planting Will Increase Soybean Insect Threat
June 12, 2017
Higher than average temperatures this past winter affected much of the nation, especially the South and Midwest. The National Centers 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
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
Latest News
Young Corn Plants
Eric SfiligojLaunching New Seed Traits: Wait on China . . . Or Else!
June 26, 2017
In life, no one likes the waiting game. In agriculture, however, playing the waiting game is very important – especially Read More
Monsanto sign
Crop InputsMonsanto Speaks on Dicamba Issues in Arkansas
June 26, 2017
Monsanto’s Chief Technology Officer, Robb Fraley, issued the following statement following the Arkansas State Plant Board’s proposal to ban dicamba, Read More
Corn Field
Seed/BiotechCorn Insect Bt Technologies Offer Cost-effective, Proac…
June 26, 2017
When farm economics are challenging, farmers look for ways to bolster profit margins, including reducing input costs. Some may think Read More
Crop InputsArkansas Plant Board Votes to Ban Dicamba — Now W…
June 23, 2017
The Arkansas State Plant Board has voted to pass a proposed emergency rule to ban the use of in-crop dicamba, Read More
Engenia soybeans
Crop InputsBASF: ‘Closely Monitoring’ Dicamba Situatio…
June 22, 2017
BASF, whose Engenia herbicide is the target of more than 200 drift complaints in Arkansas, emailed the following statement to Read More
ManagementConsolidation Update
June 22, 2017
Editors Paul Schrimpf and Eric Sfiligoj discuss progress on manufacturer consolidation, and another big move for Midwest cooperative Central Valley Read More
Palmer pigweed seedhead in cotton
Crop InputsThreat of Dicamba Ban Looms in Arkansas
June 22, 2017
The Arkansas State Plant Board has rejected a proposed ban on the use of dicamba herbicide, but a procedural error Read More
Potash Agrium
Crop InputsAgrium-PotashCorp to become Nutrien upon Merger Complet…
June 21, 2017
Potash Corporation of Saskatchewan Inc. and Agrium Inc. have announced today that once the anticipated merger transaction closes, the new Read More
Crop InputsMidwestern BioAg Hosts TerraNu Fertilizer Plant Opening…
June 20, 2017
Last Friday, Midwestern BioAg was joined by over 80 local farmers, media and staff to celebrate the grand opening of Read More
Soybean Field
Industry NewsAligned Ag Distributors Names New President
June 19, 2017
Aligned Ag Distributors LLC announced this morning the appointment of Mary Tolke to the position of President/CEO, effective July 1. Read More
ManagementPlotting Corn, AGCO/Asmark’s Applicator Training Center…
June 15, 2017
Editors Paul Schrimpf and Eric Sfiligoj talk about their recent visits to Columbus, OH, and Bloomington, IL, along with an Read More
Seed/BiotechDow AgroSciences Announces Launch of Enlist Corn for 20…
June 14, 2017
Enlist corn will be commercially available in the U.S. for the 2018 growing season. Dow AgroSciences announced the launch today Read More
ASMARK AGCO Applicator Training Center
EmployeesAsmark, AGCO Open Training Center for Beginning Applica…
June 13, 2017
AGCO Corp. and the Asmark Institute have opened a new Applicator Training Center, created in a collaboration between the two Read More
Power to Do More Contest Winners
HerbicidesDow AgroSciences Announces Three Winners in Power to Do…
June 13, 2017
Thousands of votes have been cast and three farmers have been awarded the power to do more with a $10,000 Read More
Frogeye leaf spot
FungicidesStrobilurin-resistant Frogeye Leaf Spot Threat Looms wi…
June 13, 2017
Heavy spring rainfall throughout the South and Midwest delayed planting and created the perfect environment for diseases like frogeye leaf Read More
PrecisionAg Vision Conference
Precision AgPrecisionAg® Vision Conference: Focused on the Future
June 13, 2017
PrecisionAg® is pleased to announce the return of its PrecisionAg Vision Conference, October 10-12, 2017. Based on overwhelmingly positive response Read More
CHS St. Paul, MN fertilizer terminal
LegislationICGA Praises President Trump’s Remarks on Waterwa…
June 12, 2017
Illinois Corn Growers Association President Justin Durdan, a farmer from Utica, issued the following statement regarding President Donald Trump’s comments Read More
Wheat Growers
UncategorizedWheat Growers Names Tracy Linbo as Senior Vice Presiden…
June 12, 2017
Wheat Growers has hired Tracy Linbo as Senior Vice President of Agronomy. Linbo joins Wheat Growers after having served 10 Read More