Tag Archives: Weed of the Month

Weed of the Month: Cocklebur

  • Common name: Common cocklebur
  • Scientific name: Xanthium strumarium1
  • Life cycle: Summer annual1
  • Seedlings: Stem is purple in color with large cotyledons.
  • Leaf arrangement: Early leaves are arranged in an opposite pattern; mature leaves are arranged in an alternate pattern.

Fast facts

  • Common cocklebur can grow between 2 to 4 feet tall.2
  • Common cocklebur can be found in agricultural fields, on roadsides, in ditches, in pastures, in orchards and in unmanaged places.2
  • Each bur contains two seeds — with one larger than the other.1
  • Cocklebur seeds and seedlings can be fatal to livestock if the animal ingests 1% or more of its body weight.2
  • Mature plants have thick stems with purple or black spots.2
  • The leaves of the mature plant have a distinct scent.2
  • Male flowers are red and form in clusters with female flowers below on the stalk. Cocklebur flowers during the months of July to October.2
  • The cocklebur seeds are brown, egg-shaped and prickly.1

Resistance statistics*

  • According to WeedScience.org, herbicide-resistant common cocklebur has been discovered in 15 states:* Alabama, Arkansas, Illinois, Iowa, Kansas, Louisiana, Maryland, Minnesota, Mississippi, Missouri, North Carolina, Ohio, Oklahoma, South Carolina and Tennessee.

*Resistance confirmation does not include all weeds and may vary among different areas of each state.

Corteva Agriscience, Agriculture Division of DowDuPont, offers the following weed control solutions:

Corn Herbicides

DuPont Cinch® ATZ herbicide
DuPont Realm® Q herbicide
Durango® DMA® herbicide
Elevore® herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One® herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean Herbicides
Durango® DMA® herbicide
DuPont EverpreX® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One® herbicide, as part of the Enlist weed control system
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide
DuPontAfforia® herbicide
DuPontEnlite® herbicide
DuPont™ FeXapan™ herbicide Plus VaporGrip® Technology
DuPont Trivence® herbicide


Sources:

1University of Illinois Extension and Outreach, Department of Crop Sciences. 2019. Common Cocklebur. http://extension.cropsciences.illinois.edu/fieldcrops/weeds/common_cocklebur/
2University of California Agriculture and Natural Resources, Statewide Integrated Pest Management. 2019. Common Cocklebur. http://ipm.ucanr.edu/PMG/WEEDS/common_cocklebur.html

Additional Resource:

University of Missouri Division of Plant Sciences, Weed ID Guide. 2018. Common Cocklebur: Xanthium strumarium.https://weedid.missouri.edu/weedinfo.cfm?weed_id=314

Corteva Agriscience, the Corteva Agriscience Logo, Afforia, Cinch, DMA, DuPont, Durango, Elevore, Enlist, Enlist Duo, Enlist One, Enlite, EverpreX, FeXapan, FirstRate, FulTime, Keystone, Realm, Resicore, Sonic, SureStart, Surveil and Trivence are trademarks of Dow AgroSciences, DuPont or Pioneer, and their affiliated companies or their respective owners. VaporGrip® is a registered trademark of the Bayer Group. Cinch ATZ, FeXapan, FulTime NXT, Keystone LA NXT and Keystone NXT are Restricted Use Pesticides. Durango DMA, Elevore, FeXapan, FulTime NXT, Keystone LA NXT, Resicore, Sonic, SureStart II and Surveil are not registered for sale or use in all states. Keystone NXT is not available for sale, distribution or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. EverpreX is not registered in all states. See your DuPont retailer or representative for availability in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. Consult Enlist herbicide labels for weed species controlled. Always read and follow label directions. ©2019 Dow AgroSciences LLC

Weed of the Month: Common Lambsquarters

  • Common LambsquartersCommon name: Common lambsquarters
  • Scientific name: Chenopodium album1
  • Grass or broadleaf: Summer annual broadleaf1
  • Germination timing: Common lambsquarters emerges early in the growing season, so it is key to control this weed with a postemergence herbicide prior to reaching maximum control heights.1
  • The seeds of common lambsquarters can remain dormant for many years. Fifty percent of seeds have been found to survive for 12 years, 32 percent have been found to survive for 20 years and one percent of seeds has been found to last 78 years.1
  • The cotyledons and early leaves appear blue-green on the top and a purple-red on the underside of the leaf.2

Fast facts

  • Common lambsquarters can grow up to five feet tall.2
  • Night tilling, also known as dark tillage, will reduce the emergence by 30 percent to 70 percent.1
  • Including small grains into crop rotation can suppress the growth of lambsquarters.1
  • Mature common lambsquarters’ leaves are pale green, triangular and up to 2 inches in length.2
  • The new leaves on common lambsquarters can be identified by their white, waxy coating.2
  • Common lambsquarters can produce 30,000-176,000 seeds per plant.1
  • The flowers of the common lambsquarters bloom from May to November.2

Resistance statistics*

  • According to WeedScience.org, herbicide-resistant common lambsquarters (mostly to PSII (WSSA Group 5) inhibitors) has been discovered in 22 states:* Connecticut, Delaware, Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Tennessee, Vermont, Virginia, Washington, West Virginia and Wisconsin.

*Resistance confirmation does not include all weeds and may vary among different areas of each state.

Corteva Agriscience, Agriculture Division of DowDuPont, offers the following weed control solutions:

Corn Herbicides

DuPont Cinch® ATZ herbicide
Durango® DMA® herbicide
Elevore® herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
DuPont Realm® Q herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean Herbicides
Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
DuPont EverpreX® herbicide
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide
DuPont Trivence® herbicide
DuPontEnlite® herbicide
DuPontAfforia® herbicide
DuPont™ FeXapan™ herbicide Plus VaporGrip® Technology


Sources:

1Michigan State University, Department of Plant, Soil and Microbial Sciences 2019. Common Lambsquarters. https://www.canr.msu.edu/weeds/extension/common-lambsquarters
2University of California Integrated Pest Management 2019. Common lambsquarters.  http://ipm.ucanr.edu/PMG/WEEDS/lambsquarters.html

®™Trademarks of Dow AgroSciences, DuPont or Pioneer, and their affiliated companies or their respective owners. Cinch ATZ, FeXapan, FulTime NXT, Keystone LA NXT and Keystone NXT are federally Restricted Use Pesticides. Cinch ATZ, Durango DMA, Elevore, FulTime NXT, Keystone LA NXT, Realm, Resicore, Sonic, SureStart II, Surveil and Trivence are not registered for sale or use in all states. Keystone NXT is not available for sale, distribution or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. DuPont™ FeXapan® herbicide Plus VaporGrip® Technology is not registered for sale in all states. Contact your local DuPont retailer or representative for details and availability in your state. EverpreX is not registered in all states. See your DuPont retailer or representative for availability in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. Consult Enlist herbicide labels for weed species controlled. Always read and follow label directions. ©2019 Dow AgroSciences LLC

Weed of the Month: Marestail

  • marestailCommon name: Marestail, horseweed, Canada fleabane
  • Scientific name: Conyza canadensis 1
  • Grass or broadleaf: Annual broadleaf
  • Germination timing: Marestail can begin its growing season in fall or spring. Plants that emerge in the fall can survive the winter and continue growing as the row crop emerges.2
  • Marestail begins its growth cycle as a small rosette between one to four inches across. While scouting, it is important to look beneath debris because the plants may otherwise remain hidden.3
  • Many states in the Midwest are fighting the ever-growing population of marestail that is resistant to glyphosate and ALS-inhibiting herbicides.3

Fast facts

  • Marestail can grow up to six feet tall. Once a plant grows up to five inches, control becomes much more difficult.2
  • Each plant can produce 200,000 seeds per plant—which are spread primarily by wind—that can travel to neighboring farms and even nearby states.2
  • According to WeedScience.org, the first confirmation of glyphosate-resistant horseweed was in Delaware in 2000. Since then, resistance has spread across the Midwestern states.
  • Corn and small grains can help control marestail. The canopy of corn can suppress growth, while small grains can be highly competitive. 2

Weed management tips

  • Use a herbicide in the fall: an application of a burndown herbicide in the fall season can aid in marestail control. It is best to apply the herbicide with temperatures above 50 degrees and with low wind.1
  • Scout your fields: By checking the fields before or immediately after harvest, farmers can make plans to control marestail with a fall or spring herbicide.1
  • Plant a cereal rye cover crop: This crop can provide a mulch that will suppress marestail emergence.1
  • Apply a herbicide in the spring: This practice can control weeds that have grown throughout the winter and suppress emergence of any new weeds. Use a burndown herbicide mixed with a residual herbicide for best results.3

Resistance statistics*

  • According to WeedScience.org, herbicide-resistant marestail has been documented in almond, blueberry, corn, cotton, grapes, rice, soybean and wheat production in 25 states: Alabama, Arkansas, California, Delaware, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Michigan, Mississippi, Missouri, Montana, Nebraska, New Jersey, North Carolina, Ohio, Oklahoma, Pennsylvania, South Dakota, Tennessee, Virginia, Wisconsin and West Virginia.

*Resistance confirmation does not include all weeds and may vary among different areas of each state.

Corteva Agriscience, Agriculture Division of DowDuPont, offers the following weed control solutions:

Corn Herbicides

DuPont Cinch® ATZ herbicide
Durango® DMA® herbicide
Elevore® herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
DuPont Realm® Q herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean Herbicides
Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
DuPont EverpreX® herbicide
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide
DuPont Trivence® herbicide
DuPontEnlite® herbicide
DuPontAfforia® herbicide
DuPont™ FeXapan™ herbicide Plus VaporGrip® Technology


Sources:

1Integrated Crop Management News and Iowa State University Extension and Outreach 2017. Fall Marestail (Horseweed) Management. https://crops.extension.iastate.edu/cropnews/2017/10/fall-marestail-horseweed-management
2 Penn State Extension 2017. Marestail (Horseweed) Management. https://extension.psu.edu/marestail-horseweed-management
3Nebraska Institute of Agriculture and Natural Resources 2016. Fall is Optimal for Marestail Management. https://cropwatch.unl.edu/2016/fall-optimal-marestail-management

 

®™℠Trademarks and service marks of Dow AgroSciences, DuPont or Pioneer, and their affiliated companies or their respective owners. Cinch ATZ, FeXapan Plus VaporGrip Technology and Keystone LA NXT are Restricted Use Pesticides. Durango DMA, Elevore, EverpreX, FulTime NXT, Keystone NXT, Realm, Resicore, Sonic, SureStart II, Surveil and Trivence are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. DuPont™ FeXapan™ herbicide plus VaporGrip® Technology is a Restricted Use Pesticides. DuPont™ FeXapan™ herbicide plus VaporGrip® Technology is not registered for sale or use in all states. IT IS A VIOLATION OF FEDERAL AND STATE LAW TO MAKE AN IN-CROP APPLICATION OF ANY DICAMBA HERBICIDE PRODUCT ON SOYBEANS WITH Roundup Ready 2 Xtend® technology, OR ANY OTHER PESTICIDE APPLICATION, UNLESS THE PRODUCT LABELING SPECIFICALLY AUTHORIZES THE USE. Contact the U.S. EPA and your state pesticide regulatory agency with any questions about the approval status of dicamba herbicide products for in-crop use with soybeans with Roundup Ready 2 Xtend® technology and follow all pesticide product labeling. Soybeans with Roundup Ready 2 Xtend® technology contain genes that confer tolerance to glyphosate and dicamba. Glyphosate herbicides will kill crops that are not tolerant to glyphosate. Dicamba will kill crops that are not tolerant to dicamba. Roundup Xtend®, VaporGrip®, Roundup Ready 2 Xtend® (Monsanto). VaporGrip® Technology is used under license from Monsanto Technology LLC. Always read and follow label directions. ©2019 Dow AgroSciences LLC

Weed of the Month: Giant Ragweed

  • giant ragweedCommon name: Giant ragweed
  • Scientific name: Ambrosia trifida1
  • Grass or broadleaf: Annual broadleaf
  • Giant ragweed grows in the Midwest and Eastern regions of the United States, but it is most heavily concentrated in the eastern Corn Belt states like Indiana and Illinois.2
  • Germination timing: Giant ragweed is traditionally an early season weed; however, its growing season is expanding. Giant ragweed typically sprouts in early May but has been seen as early as March. The weed can continue to cause issues through late July and can impede harvest if not controlled.2
  • Competitiveness: Giant ragweed is one of the most competitive weeds in corn and soybeans.
    • Two giant ragweed plants within a 110 square feet area can reduce corn yield by 13 percent.2
    • Soybean yield can be reduced by 50 percent when there is just one giant ragweed plant within a 110 square foot area.2
  • Giant ragweed can grow 1-5 feet taller than competing plants and can reach heights of up to 17 feet tall.2

Fast facts

  • When a giant ragweed plant first emerges, it can be identified by its spatulate cotyledons. These cotyledons are spoon-shaped and can range from 1 to 1 ¾ inches long.2
  • Giant ragweed always has three distinct lobes but can show up to five lobes that grow in an opposite arrangement.2
  • According to WeedScience.org, the first confirmation of herbicide resistant giant ragweed in the United States was in an Indiana soybean field in 1998.
  • Giant ragweed is a monoecious plant, which means that separate male and female flowers can found on a single plant.2
  • Giant ragweed seeds can be identified by their points and ridges that make them look like small crowns.2

Weed management tips2

  • Use multiple modes of action:
    • One of the best ways to fight giant ragweed is to use multiple modes of action in a herbicide program with both preemergence and postemergence herbicides.
  • Scout for weeds:
    • Look for giant ragweed two weeks after the postemergence herbicide application and determine if another application is needed.

Resistance Statistics*

  • According to to WeedScience.org, herbicide-resistant giant ragweed has been documented in corn and soybean fields in 13 states: Arkansas, Illinois, Indiana, Iowa, Kansas, Kentucky, Minnesota, Mississippi, Missouri, Nebraska, Ohio, Tennessee and Wisconsin.*

*Resistance confirmation does not include all weeds and may vary among different areas of each state.

Here are a few of the weed control solutions from Corteva Agriscience, Agriculture Division of DowDuPont:

Corn

DuPont Cinch® ATZ herbicide
Durango® DMA® herbicide
Elevore® herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
Keystone® NXT herbicide
DuPont Realm® Q herbicide
Resicore® herbicide
SureStart® II herbicide
FulTime herbicide

Soybean

Durango® DMA® herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FirstRate® herbicide
Sonic® herbicide
DuPont Trivence® herbicide
DuPontEnlite® herbicide
DuPontAfforia® herbicide
DuPont™ FeXapan™ herbicide Plus VaporGrip® Technology

Additional information:

For more information, read these weed science resources:

Sources:
1University of Missouri Division of Plant Sciences 2018. Weed ID Guide, Giant Ragweed. https://weedid.missouri.edu/weedinfo.cfm?weed_id=18
2 University of Missouri 2014. Biology and Management of Giant Ragweed. https://weedscience.missouri.edu/publications/gwc-12.pdf

®™Trademark of The Dow Chemical Company (“Dow”) or E. I. du Pont de Nemours and Company (“DuPont”) or affiliated companies of Dow or DuPont. Cinch ATZ, FeXapan Plus VaporGrip Technology and Keystone NXT are federally Restricted Use Pesticides. Durango DMA, Elevore, EverpreX, FulTime NXT, Keystone NXT, Realm, Resicore, Sonic, SureStart II, Surveil and Trivence are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. DuPont™ FeXapan™ herbicide plus VaporGrip® Technology is a restricted-use pesticide. DuPont™ FeXapan™ herbicide plus VaporGrip® Technology is not registered for sale or use in all states. Contact your DuPont retailer or representative for details and availability in your state. IT IS A VIOLATION OF FEDERAL AND STATE LAW TO MAKE AN IN-CROP APPLICATION OF ANY DICAMBA HERBICIDE PRODUCT ON SOYBEANS WITH Roundup Ready 2 Xtend® technology, OR ANY OTHER PESTICIDE APPLICATION, UNLESS THE PRODUCT LABELING SPECIFICALLY AUTHORIZES THE USE. Contact the U.S. EPA and your state pesticide regulatory agency with any questions about the approval status of dicamba herbicide products for in-crop use with soybeans with Roundup Ready 2 Xtend® technology and follow all pesticide product labeling. Soybeans with Roundup Ready 2 Xtend® technology contain genes that confer tolerance to glyphosate and dicamba. Glyphosate herbicides will kill crops that are not tolerant to glyphosate. Dicamba will kill crops that are not tolerant to dicamba. Roundup Xtend® , VaporGrip® , Roundup Ready 2 Xtend® (Monsanto). VaporGrip® Technology is used under license from Monsanto Technology LLC. Always read and follow label directions. ©2018 Dow AgroSciences LLC

Weed of the Month: Palmer Amaranth

  • Palmer AmaranthCommon name: Palmer pigweed
  • Scientific name: Amaranthus palmeri 1
  • Grass or broadleaf: Annual broadleaf
  • Native to the Southwestern desert regions of the United States, Palmer amaranth has expanded rapidly across the Southeast and can be found in multiple Midwestern states.1
  • Germination timing: Palmer amaranth emergence is from early May until mid-September. This long emergence period forces farmers to manage the weed throughout the year, unlike other summer annual weeds that are typically managed only through early summer.1
  • Competitiveness: Known as the most competitive and aggressive pigweed species, Palmer amaranth can lead to soybean yield loss up to 79 percent and corn yield loss up to 91 percent in some states. It also can significantly increase production costs.2
  • Palmer amaranth grows fast – as much as 2 to 3 inches per day – and commonly reaches 6 to 8 feet.2
  • Farm equipment, specifically combines, and wildlife can spread Palmer amaranth seed into new, previously uninfected fields.1

Fast facts

  • Palmer amaranth has dioecious reproduction, meaning plants are either male or female, which forces outcrossing and genetic diversity.1 This makes it more difficult to control.
  • Each plant can produce 100,000 or more seeds when it competes with a crop. In noncompetitive scenarios, each plant can produce nearly a half million seeds.
  • According to WeedScience.org, the first confirmation of glyphosate-resistant Palmer amaranth in Midwest corn, cotton and soybean fields occurred in Missouri in 2008.
  • To identify Palmer amaranth, look for smooth green leaves arranged in an alternate pattern that grows symmetrically around the stem. The leaves are oval to diamond-shaped. There may be a small, sharp spine at the leaf tip.2
  • Palmer amaranth seeds are small and thrive in no-till or minimum-tillage fields.1

Weed management tips1

  • Rotate crops: this allows farmers to use herbicides with additional modes of action in the field.
  • Practice deep tillage: this will bury the small Palmer amaranth seed below its preferred emergence depth.
  • Plant a cereal rye cover crop: this crop can provide a mulch that will suppress Palmer amaranth emergence.
  • Harvest heavily infested fields last: because machinery so easily spreads Palmer amaranth seeds from one field to another, consider harvesting fields or parts of field with infestations last to limit seeds to that area.

Resistance Statistics*

  • According to WeedScience.org, herbicide-resistant Palmer amaranth has been documented in corn and soybean fields in 24 states: Alabama, Arkansas, California, Delaware, Florida, Georgia, Illinois, Kansas, Kentucky, Louisiana, Maryland, Michigan, Missouri, Nebraska, New Jersey, New Mexico, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Texas, Virginia and Wisconsin.

*Resistance confirmation does not include all weeds and may vary among different areas of each state.

Corteva Agriscience, Agriculture Division of DowDuPont, offers the following weed control solutions:

Corn

DuPont Cinch® ATZ herbicide
Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
DuPont Realm® Q herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean

Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
DuPont EverpreX® herbicide
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide
DuPont Trivence® herbicide

Additional information:

For more information, read these weed science resources:

Sources:
1Purdue University Extension 2013. Palmer Amaranth Biology, Identification, and Management. https://www.extension.purdue.edu/extmedia/WS/WS-51-W.pdf
2Minnesota Department of Agriculture 2018. Palmer Amaranth in Minnesota. https://mda.state.mn.us/plants-insects/palmer-amaranth-minnesota

®™Trademark of The Dow Chemical Company (“Dow”) or E. I. du Pont de Nemours and Company (“DuPont”) or affiliated companies of Dow or DuPont. Cinch ATZ, FulTime NXT, Keystone LA NXT and Keystone NXT are federally Restricted Use Pesticides. Cinch ATZ, Durango DMA, Elevore, EverpreX, FulTime NXT, Keystone LA NXT, Keystone NXT, Realm, Resicore, Sonic, SureStart II, Surveil and Trivence are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. Always read and follow label directions. ©2018 Dow AgroSciences LLC

Weed of the Month: Waterhemp

  • waterhempVarious types: Common1
  • Scientific name: Amaranthus rudis1
  • Member of the pigweed (Amaranthaceae) family1
  • Grass or broadleaf: Broadleaf
  • Commonly found in Midwest states — native to North America1
  • Growing period: mid-May to early July3
  • Plants are male or female2

Fast facts:

  • Waterhemp can reduce yield by 74 percent in corn and 56 percent in soybeans if left unmanaged, according to Wisconsin Crop Weed Science, University of Wisconsin-Madison.1
  • Female plants produce 250,000 seeds per plant. However, one plant can produce up to 1 million seeds if there is little to no plant competition.2
  • Waterhemp can grow between 1 and 1.25 inches per day during the growing season, which is faster than most crops or weeds.2
  • Waterhemp seeds must be in the top inch of soil to successfully germinate and emerge.3
  • Waterhemp is a “multiple herbicide-resistant weed,” which means it cannot be controlled by at least two or more herbicides with different sites of action applied at labeled rates.4

Resistance Statistics:*

According to WeedScience.org:

As of June 2018, herbicide-resistant waterhemp has been reported in the following 18 states, listed in alphabetical order:

  • Arkansas, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, Oklahoma, South Dakota, Tennessee, Texas, Wisconsin

Managing waterhemp:

  • Tillage can help lower waterhemp populations because the seeds must germinate in the top part of the soil; however, tillage may not be a viable method of control on land prone to erosion.3
  • Narrower row spacing can help suppress waterhemp growth.3

Andy Asbury, field scientist, Corteva Agriscience, Agriculture Division of DowDuPont, Dow AgroSciences, offers advice:

  • Farmers should scout throughout the growing season to identify waterhemp early. This helps farmers plan timely herbicide applications and identify potential problem fields for the following year.
  • The best strategy to control waterhemp involves combining aggressive tillage and a program approach to herbicide application — including soil-applied herbicides followed by postemergence herbicide(s) with multiple, effective modes of action. Ideally, you would overlap preemergence residuals and postemergence residuals to reduce the number of germinating waterhemp plants.

Corteva Agriscience, Agriculture Division of DowDuPont, offers the following weed control solutions:

Corn

DuPont Cinch® ATZ herbicide
DuPont Realm® Q herbicide
Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean

Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
DuPont EverpreX® herbicide
DuPont Trivence® herbicide
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide

Additional information:

For more information, read these weed science resources:

  1. Butts, T. R., and V. M. Davis. 2014. Preliminary data suggests glyphosate resistance of two Wisconsin common waterhemp (Amaranthus rudis) populations. https://wcws.cals.wisc.edu/tag/amaranthus-rudis
  2. Bechman, T. J. 2017. 8 facts you should know about waterhemp in Indiana. http://www.indianaprairiefarmer.com/weeds/8-facts-you-should-know-about-waterhemp-indian
  3. Pioneer. Effective Management of Waterhemp. https://www.pioneer.com/home/site/us/agronomy/waterhemp-mgmt-soybean
  4. Ganie, Z., and J. Amit. Multiple Herbicide-Resistant Weeds and Challenges Ahead. https://cropwatch.unl.edu/multiple-herbicide-resistant-weeds-and-challenges-ahead

®™Trademarks of Dow AgroSciences, DuPont or Pioneer and their affiliated companies or respective owners. DuPont Cinch® ATZ, FulTime NXT, Keystone LA NXT and Keystone NXT are federally Restricted Use Pesticides. DuPont Cinch® ATZ herbicide, DuPont EverpreX herbicide, DuPont Realm® Q herbicide, DuPont Trivence® herbicide, Durango DMA, Elevore, FirstRate, FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore, Sonic, SureStart II and Surveil are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. Always read and follow label directions. ©2018 Corteva Agriscience

Weed of the month: Lambsquarters

  • lambsquartersVarious types: Common1
  • Scientific name: Chenopodium album1
  • Grass or broadleaf: Broadleaf
  • Found in all states
  • Germination timing: Summer annual. Lambsquarters emerges in the spring, sets seed in late summer/fall and dies.2
  • Competitiveness: Common lambsquarters is a highly competitive weed. Michigan State University reports 13 percent yield loss in corn with one lambsquarters plant per 1½ feet of row and 25 percent yield loss in soybeans with less than one plant per foot of row.2
  • Lambsquarters grows to 3½ feet in height and produces thousands of seeds.3

Fast Facts

  • Lambsquarters is a cool-season, early germinating annual broadleaf weed that can be most problematic in northern areas, says Jeff Ellis, field scientist, Corteva Agriscience, Agriculture Division of DowDuPont, Dow AgroSciences. Identify lambsquarters by looking for a white, “frosted” appearance of upper leaves.
  • According to WeedScience.org, the first confirmation of triazine-resistant lambsquarters in the United States occurred in Michigan in 1975. Today, lambsquarters is resistant to one or more sites of action in 22 states.
  • Cotyledons of common lambsquarters and redroot pigweed are similar; however, redroot pigweed cotyledons have a prominent midvein while lambsquarters cotyledons do not.3

Resistance statistics:*

  • Herbicide classes

    *Resistance confirmation does not include all weeds and may vary among different areas of each state.

Weed management tips:

Ellis says:

  • It’s important to scout for lambsquarters early because it tends to germinate early in the spring under cooler conditions.
  • Lambsquarters is difficult to control with glyphosate, especially when it grows larger than 3 or 4 inches.
  • The most effective lambsquarters control strategy requires a program approach with preemergence herbicides followed by early postemergence herbicide applications.

Corteva Agriscience, Agriculture Division of DowDuPont, weed control solutions:

Corn

DuPont Cinch® ATZ herbicide
DuPont Realm® Q herbicide
Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
FulTime® NXT herbicide
Keystone® LA NXT herbicide
Keystone® NXT herbicide
Resicore® herbicide
SureStart® II herbicide

Soybean

Durango® DMA® herbicide
Elevore herbicide
Enlist Duo® herbicide, as part of the Enlist weed control system
Enlist One herbicide, as part of the Enlist weed control system
DuPont EverpreX® herbicide
DuPont Trivence® herbicide
FirstRate® herbicide
Sonic® herbicide
Surveil® herbicide

Additional information:

For more information, read these weed science resources:

Sources:

1U.S. Department of Agriculture Natural Resources and Conservation Service. 2018. Plant Profile: Chenopodium album L. lambsquarters. http://plants.usda.gov/core/profile?symbol=chal7
2MSU Department of Plant, Soil and Microbial Sciences. 2018. Common Lambsquarters. https://www.canr.msu.edu/weeds/extension/common-lambsquarters
3University of Missouri Division of Plant Sciences. 2018. Common Lambsquarters. https://weedid.missouri.edu/weedinfo.cfm?weed_id=60

®™Trademark of The Dow Chemical Company (“Dow”) or E. I. du Pont de Nemours and Company (“DuPont”) or affiliated companies of Dow or DuPont. DuPont Cinch® ATZ, FulTime NXT, Keystone LA NXT and Keystone NXT are federally Restricted Use Pesticides. DuPont Cinch® ATZ herbicide, DuPont EverpreX herbicide, DuPont Realm® Q herbicide, DuPont Trivence®, Durango DMA, Elevore, FirstRate, FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore, Sonic, SureStart II and Surveil are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, Resicore and SureStart II are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Enlist Duo and Enlist One herbicides are not registered for sale or use in all states or counties. Contact your state pesticide agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One herbicides are the only 2,4-D products authorized for use in Enlist crops. Always read and follow label directions. ©2018 Dow AgroSciences LLC