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

Syngenta Sign
FungicidesSyngenta’s Newest Fungicide Receives EPA Approval
September 1, 2015
Syngenta announced today that its newest succinate dehydrogenase inhibitor (SDHI) fungicide – Solatenol – has received registration from EPA and Read More
Flooded corn in Indiana
Crop InputsDelaying The Fertilizer Decision
September 1, 2015
Comments gathered from several retailers recently evidenced a classic good-news-bad-news scenario. Good news is prices and supplies of nitrogen, phosphate, Read More
Crop InputsMonsanto, FMC Expand Roundup Ready PLUS Platform
August 31, 2015
FMC Corp. and Monsanto Co. announced today an expanded agreement to continue their participation in the Roundup Ready PLUS Crop Read More
FertilizerFall-Applied Phosphorus: A Rooted Investment
August 28, 2015
As commodity prices decrease and input prices continue to rise, farmers are seeking more efficient strategies for meeting a high Read More
Top 100 Articles
Crop InputsLand ‘O Lakes, United Suppliers Finalize Merger
August 24, 2015
According to a press release on August 24, owners of United Suppliers, Inc. and members of Land O’Lakes, Inc. “have Read More
West Central Cooperative, Jefferson, IA
CropLife 100Iowa Cooperatives To Explore Unification
August 19, 2015
The boards of directors at two of Iowa’s leading farmer-owned cooperatives yesterday signed a letter of intent to study the Read More
CropLife 100Southern States Coop Hosting Drone Flight This Friday
August 3, 2015
Southern States Cooperative — No. 9 on the CropLife 100 — is hosting an FAA-approved drone demonstration at Grandview Farms Read More
CropLife 100Aligned Ag Distributors Adds Four New Owners
July 30, 2015
Aligned Ag Distributors LLC has announced the addition of four new customer/owners to Franklin Holding Co. LLC. They are: The Read More
CropLife 100Pinnacle Purchases California-Based Specialty Crops Retailer
July 20, 2015
Pinnacle Agriculture Holdings has successfully acquired California-based NH3 Service Co.  Operating as part of Pinnacle’s Performance Agriculture brand, the new locations Read More
Asmus Farm Supply liquid fertilizer facility features 20,000 square feet
CropLife 100Slideshow: Asmus Farm Supply Shows Off Its New Liquid Fertilizer Facility
July 15, 2015
Asmus Farm Supply, Rake, IA, recently added a new liquid fertilizer facility to its company operations. The new liquid fertilizer Read More
Latest News
SprayersNORAC Active Wing Roll Slated For More Sprayers
September 1, 2015
NORAC Systems, a member of the Topcon Positioning Group, announces the release of Active Wing Roll for RoGator, Apache, New Read More
Syngenta Sign
FungicidesSyngenta’s Newest Fungicide Receives EPA Approval
September 1, 2015
Syngenta announced today that its newest succinate dehydrogenase inhibitor (SDHI) fungicide – Solatenol – has received registration from EPA and Read More
Flooded corn in Indiana
Crop InputsDelaying The Fertilizer Decision
September 1, 2015
Comments gathered from several retailers recently evidenced a classic good-news-bad-news scenario. Good news is prices and supplies of nitrogen, phosphate, Read More
StewardshipBee Buffer Strip Initiative Seeks 100 Ohio Farmers
August 31, 2015
The U.S. Bee Buffer Project, an initiative of the Pollinator Partnership (P2), Burt’s Bees and The Burt’s Bees Greater Good Read More
2015 ShowStopper Award, MAGIE
EquipmentA ShowStopper From Case IH: The Patriot 2250
August 31, 2015
For nine years now, visitors to the yearly Midwest AG Industries Exposition (MAGIE) show have been tasked with not only Read More
Crop InputsMonsanto, FMC Expand Roundup Ready PLUS Platform
August 31, 2015
FMC Corp. and Monsanto Co. announced today an expanded agreement to continue their participation in the Roundup Ready PLUS Crop Read More
Deere Nutrient Applicator
Eric SfiligojThe Good & Bad News From MAGIE
August 31, 2015
As I write this column, I’ve just returned from the annual Midwest AG Industries (MAGIE) trade show in Bloomington, IL. Read More
CPS Morenci receiving its 4R certification
StewardshipCPS Morenci Becomes First Michigan Facility Certified I…
August 31, 2015
The 4R Nutrient Stewardship Certification Program has announced that Crop Production Services, Inc.’s facility located in Morenci, MI, has been Read More
EquipmentDeere Announces Soucy Track Distribution Alliance
August 28, 2015
John Deere announces an alliance with Soucy Track to sell and distribute products through the John Deere dealer channel. “This Read More
FertilizerFall-Applied Phosphorus: A Rooted Investment
August 28, 2015
As commodity prices decrease and input prices continue to rise, farmers are seeking more efficient strategies for meeting a high Read More
Monsanto Sign
Crop InputsWhat’s Next For Monsanto, Syngenta?
August 28, 2015
After dropping its $47 billion bid to take over Swiss agribusiness firm Syngenta, Monsanto may be turning its focus to Read More
Golden Harvest Corn stalks
Crop InputsMonsanto: Syngenta Not The Only Horse In Crop Protectio…
August 28, 2015
Monsanto Co, having ditched an audacious $46 billion (£30 billion) offer for Syngenta AG, may downshift to a humbler strategy Read More
ManagementConsolidation hits and a miss; And a look at China’s ch…
August 28, 2015
As Monsanto suspends its pursuit of Syngenta, consolidation news at the retail and distribution level heats up. CropLife magazine’s Executive Read More
Corn Field
MicronutrientsHuma Gro Introduces New Boron Liquid Nutrient Formulati…
August 28, 2015
BORO-MAX, a new boron (B) 10% liquid nutrient formulation, has been added to the Huma Gro product line. This new Read More
Crop InputsNFU: Monsanto Decision To Withdraw Syngenta Bid ‘…
August 26, 2015
National Farmers Union (NFU) President Roger Johnson said the organization was very pleased by the news that Monsanto has withdrawn Read More
Crop InputsMonsanto Withdraws Bid For Syngenta
August 26, 2015
Monsanto Co. abandoned its latest effort to acquire Syngenta AG, the world’s top maker of pesticides, after a sweetened bid Read More
Syngenta Sign
Crop InputsSyngenta Comments On Monsanto Announcement
August 26, 2015
The Board of Syngenta confirms that it received a verbal proposal from Monsanto to acquire the company at a price Read More
Case IH Patriot 2250 Sprayer
EquipmentHigh-powered Case IH Patriot 2250 Sprayer Pushes Throug…
August 26, 2015
Engineered with more muscle, the new 660-gallon-capacity Patriot 2250 sprayer features best-in-class horsepower, along with the fuel efficiency that comes Read More