Weed Science

Weeds are major production challenge to the dryland agriculture in the U.S. Great Plains, including western Kansas. Major troublesome weeds in semiarid regions of the Great Plains include kochia, Palmer amaranth, field bindweed, horseweed, downy brome, jointed goatgrass, windmill grass, feral rye, etc. Most of these weed species infest prevalent cropping systems (winter and summer crops) in the region, steal available soil water and nutrients and cause severe grain yield loss.

Repeated use of herbicides with same modes of action for weed control has resulted in evolution and spread of herbicide-resistant weed populations in this no-tillage dryland region. For instance, Kochia and Palmer amaranth are two key weed species that have evolved widespread resistance to most commonly used herbicide: glyphosate (Roundup) in the region. In addition, several field populations of these two species have also shown multiple resistance to other herbicides. Increasing cases of herbicide-resistant weeds are serious threat to the long-term sustainability of the no-till dryland agriculture.

 

The primary aim of the weed science program under CEDA is to provide sustainable, economical and environmentally safe weed control solutions to the dryland producers in the region. Several field and laboratory-based research projects are underway at CEDA to develop integrated weed management (IWM) strategies for the dryland agriculture. For instance, projects involving field surveys and screening to monitor the herbicide resistance pattern or weed shifts in weed populations, understanding the life-history traits (including germination/emergence, growth, and seed production behavior) of problematic weeds, evaluating alternating chemicals (new PRE and POST herbicides mixtures), cultural (using new generation of stacked traits crop technologies, competitive crop rotations, cover crops, improved agronomic and other management practices) and mechanical (strategic/occasional tillage, harvest weed seed control via chaff lining and weed seed destructor) practices and evaluating precision ag tools for weed control in the region.

 

Meet our Research-Extension Specialists

• Jeremie Kouame, Assistant Professor - Weed Scientist

• Jeanne Falk Jones, Multi-County Specialist

Weed Science in the News

The New York Times Magazine publish news article on “Attack of the Superweeds” https://wssa.net/wp-content/uploads/NYT-Magazine_Attack-of-the-Superweeds_Aug-22-2021.pdf

Studies show as much as five-fold resistant shattercane in northwest Kansas
May 3, 2021
HAYS, Kan. – Kansas State University researchers are reporting that shattercane, a grass weed found in grain sorghum fields, is showing resistance to herbicides designed to stem its growth.

Vipan Kumar, a weed scientist at the K-State Agricultural Research Center in Hays, said the findings are particularly important as producers decide on whether to plant three new grain sorghum hybrids this summer. Continue Reading...

Vipan Kumar, named Outstanding Young Scientist
Dec. 11, 2020
HAYS, Kan. – Vipan Kumar, a weed science researcher at the Kansas State University Agricultural Research Center whose work has helped boost dryland cropping systems in the Great Plains region has received an early career award from the North Central Weed Science Society. Read more...

K-State Radio program discussing different herbicide programs in wheat stubble
Date: July 1, 2020
K-State weed scientist Vipan Kumar goes over the results of his herbicide field trial, which tested out a number of products for their effectiveness in controlling Palmer amaranth in post-harvest wheat stubble...he also tells of a new survey of Kansas crop producers and crop consultants he's conducting on the prevalent crop weed issues in the state. Listen to Podcast.

New study evaluated different herbicide programs in wheat stubble
Date: July 1, 2020
Recent rainfall events across various parts of Kansas have slowed down the wheat harvest, but wet soil and high temperatures have provided a conducive environment for Palmer amaranth seedbanks to germinate in standing wheat. In fact, several wheat fields with poor canopy closure have been observed with severe infestation of Palmer amaranth populations

Kansas weed survey: Producers/ag professionals input requested
Date: July 1st, 2020
Herbicide-resistant weeds are threatening the profitability and long-term sustainability of Kansas cropping systems. To help develop innovative, cost-effective, and integrated weed management practices for controlling herbicide-resistant weeds and to further improve the outreach programs for various regions of the state, the Weed Science group at the K-State Ag Research Center in Hays seeks input from Kansas producers and ag professionals (crop consultants, county agents, certified crop advisors). We invite you to please complete a brief survey related to weed management practices and herbicide-resistant weed problems. The survey will take 5-8 minutes and can be completed via this weblink: Kansas Weeds Survey

K-State scientist earns early career award for fighting weeds
March, 19, 2020
HAYS, Kan. – Vipan Kumar, an assistant professor of weed science at the Kansas State University Agricultural Research Center in Hays, received one of the top awards for young professionals during a joint meeting of the Weed Science Society of America and Western Society of Weed Science.

Weed Management Field Day - Press Release
Jun 11, 2019
HAYS, Kan. – The K-State Research and Extension Agricultural Research Center in Hays will host its annual weed management field day on Tuesday, July 2. The event will include discussions and demonstrations related to weed control in corn, soybeans, grain sorghum and sunflower. It will run from 8 a.m. to 1:30 p.m. Vipan Kumar, a weed scientist at the research center, said the field day includes demonstrations of herbicide tools for weed control in corn, and an herbicide drift simulation on soybeans.

K-State Researcher Confirm Palmer Amaranth Resistance to 2,4-D
Friday, March 8, 2019
Vipan Kumar, a weed scientist at the Agricultural Research Center in Hays, is reporting the first-ever study confirming that Palmer amaranth has developed resistance to the herbicide 2,4-D. Kumar’s findings have been published in the journal, Pest Management Science. The article, titled “Confirmation of 2,4‐D resistance and identification of multiple resistance in a Kansas Palmer amaranth (Amaranthus palmeri) population. Read the full press release.

A Review Article on Herbicide-Resistant Kochia featured by Weed Science Society of America
"A review article on herbicide-resistant kochia in North America” compiled by weed researchers from Kansas State and Montana State University has been selected as a featured article in Weed Science journal published by the Weed Science Society of America. This article has compiled information from several published studies and articles relevant to herbicide-resistant kochia, its impact and control strategies. Want to know more on this article, please read it on the Weed Science of America website.

Multiple Herbicide Resistant Palmer Amaranth in Kansas
Tuesday, January 29, 2019
Ongoing herbicide resistant Palmer Amaranth research, under the direction of Vipan Kumar, at the KSU Agricultural Research Center - Hays is featured in the recent article on the Progressive Farmer website.

Auxinic-Resistant Kochia found in Kansas
Thursday, October 11, 2018
The weed science research team at Kansas State University, under the direction of Vipan Kumar, identified Kochia biotypes that have developed cross resistance to dicamba and fluroxypyr herbicides in western Kansas. These biotypes have also been found resistant to glyphosate. To learn more about this research, continue reading on the Progressive Farmer website.

Digital Journals / Reports

1. Kumar V, Schmale D, Anderson R, Klein B (2021) Jointed goatgrass: Best management practices central Great Plains. Washington State University Extension. EB2033E. https://pubs.extension.wsu.edu/jointed-goatgrass-best-management-practices-bmp-central-great-plains
2. Kumar V, Manuchehri M, Schmale D, Peeper T, Stahlman P (2021) Jointed goatgrass: Best management practices southern Great Plains. Washington State University. EM011E. https://research.libraries.wsu.edu/xmlui/handle/2376/18764
3. Kumar V, ^*Effertz I, ^*Lambert T, ^*Liu R, Bean B (2021) Efficacy of Imiflex, Zest, and Assure II on green foxtail control. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 7: Iss. 5. https://doi.org/10.4148/2378-5977.8087
4. Kumar V, ^*Lambert T, ^*Liu R, Currie RS, Stahlman PW (2021) Auxinic herbicide mixtures for controlling multiple herbicide-resistant kochia in fallow. Field Research Report. Kansas Agricultural Experiment Station Research Reports: 7: Iss. 5. https://doi.org/10.4148/2378-5977.8088
5. ^*Liu R, ^*Effertz I, ^*Lambert T, Jhala A, Kumar V (2021) Interaction of 2,4-D with glyphosate or graminicides on grass weed control in Enlist E3 soybeans. Field Research Report. Kansas Agricultural Experiment Station Research Reports: 7: Iss. 5. https://doi.org/10.4148/2378-5977.8089
6. ^*Liu R, ^*Effertz I, ^*Lambert T, Jhala A, Kumar V (2021) Effect of tank-mixing glyphosate, dicamba, and graminicides on grass weed control in Roundup Ready 2 Xtend soybeans. Field Research Report. Kansas Agricultural Experiment Station Research Reports: 7: Iss. 5. https://doi.org/10.4148/2378-5977.8090
7. ^*Liu R, ^*Effertz I, ^*Lambert T, Kumar V (2021) Control of volunteer Enlist corn in Enlist E3 soybean. Field Research Report. Kansas Agricultural Experiment Station Research Reports: 7: Iss. 5. https://doi.org/10.4148/2378-5977.8091
8. Kumar V, ^*Liu R, ^*Lambert T (2020) Response of Kansas feral rye populations to aggressor herbicide and management in CoAXium wheat production system. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 6: Iss. 5. https://doi.org/10.4148/2378-5977.7939
9. ^*Liu R, Kumar V, ^*Aquilina N, ^*Lambert T (2020) Efficacy of late-season herbicide programs for controlling Palmer amaranth in postharvest wheat stubble. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 6: Iss. 5. https://doi.org/10.4148/2378-5977.7936
10. ^*Liu R, Kumar V, ^*Lambert T (2020) Control of multiple herbicide-resistant Palmer amaranth in Enlist corn. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 6: Iss. 5. https://doi.org/10.4148/2378-5977.7938
11. ^*Liu R, Kumar V, Currie RS, ^*Lambert T, Stahlman PW (2020) Response of dicamba/fluroxypyr/glyphosate-resistant kochia to atrazine and alternative postemergence herbicides. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 6: Iss. 5. https://doi.org/10.4148/2378-5977.7939
12. Kumar V, Lawrence N, ^*Aquilina NK, Jones JF, Creech C, Spring J (2020) Effectiveness of PRE herbicides followed by Zidua POST for controlling glyphosate-resistant weeds in High Plains sunflower production. National Sunflower Association Forum Proceedings. https://www.sunflowernsa.com/uploads/research/1357/SunflowerPaper_NSAForum_Kumar.pdf
13. Kumar V, ^*Liu R, ^*Lambert T, Stahlman PW (2019) Herbicide strategies for managing glyphosate- and dicamba-resistant kochia in Roundup Ready 2 Xtend soybean. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 5: Iss. 6. https://newprairiepress.org/kaesrr/vol5/iss6/19/
14. Kumar V, ^*Liu R, ^*Lambert T, Peterson DE, Minihan C, Stahlman PW (2019) Effective herbicide options for controlling glyphosate-resistant Palmer amaranth in Roundup Ready 2 Xtend soybean. Field Research Report. Kansas Agricultural Experiment Station Research Reports: Vol. 5: Iss. 6. https://newprairiepress.org/kaesrr/vol5/iss6/20 /
15. Kumar V, ^*Liu R, ^*Lambert T (2019) Characterization and management of glyphosate- and HPPD-inhibitor-resistant Palmer amaranth in Kansas corn production. Kansas Agricultural Experiment Station Research Reports: Vol. 5: Iss. 6. https://newprairiepress.org/kaesrr/vol5/iss6/21/
16. ^*Liu R, Kumar V, Perumal R, ^*Lambert T, Ostmeyer T (2019) Influence of cultural practices and herbicide programs for managing glyphosate-resistant Palmer amaranth in cold-tolerant sorghum. Kansas Agricultural Experiment Station Research Reports: Vol. 5: Iss. 6. https://newprairiepress.org/kaesrr/vol5/iss6/22/
17. Obour AK, Holman JD, Dille JA, Kumar V (2019) Effects of spring-planted cover crops on weed suppression and winter wheat grain yield in western Kansas. Kansas Agricultural Experiment Station Research Reports: Vol. 5: Iss. 6. https://newprairiepress.org/kaesrr/vol5/iss6/12/
18. Kumar V, Stahlman PW, ^*Boyer G (2018) Palmer amaranth populations from Kansas with multiple resistance to glyphosate, chlorsulfuron, mesotrione, and atrazine. Kansas Agricultural Experiment Station Research Reports: Vol. 4: Iss. 7. https://doi.org/10.4148/2378-5977.7611
19. Kumar, V, Stahlman PW, Currie RS, ^*Engel RS, ^*Boyer G (2018) Variable response of kochia accessions to dicamba and fluroxypyr in western Kansas. Kansas Agricultural Experiment Station Research Reports: Vol. 4: Iss. 7. https://doi.org/10.4148/2378-5977.7612

Agronomy E-Updates

1. Kumar V, Bean B (2021) Imazamox-resistant shattercane populations identified from sorghum fields in northwest Kansas (eUpdate: April 22, 2021) https://bit.ly/2QsXaaW
2. Lancaster SR, Kumar V (2021) Late winter kochia control in fields going to soybeans, sunflowers, and wheat (eUpdate: Feb 18, 2021) https://eupdate.agronomy.ksu.edu/article_new/late-winter-kochia-control-in-fields-going-to-soybeans-sunflowers-and-wheat-428-4
3. Lancaster SR, Kumar V (2021) Late winter kochia control in fields going to corn or grain sorghum (eUpdate: Feb 11, 2021) https://eupdate.agronomy.ksu.edu/article_new/late-winter-kochia-control-in-fields-going-to-corn-or-grain-sorghum-426-1
4. Lancaster SR, Kumar V (2021) Pre-plant herbicide applications for kochia control (eUpdate: Feb 4, 2021) https://eupdate.agronomy.ksu.edu/article_new/pre-plant-herbicide-applications-for-kochia-control-425-4
5. Kumar V, Bean B (2020) In-season Palmer amaranth control in grain sorghum (eUpdate: July 24, 2020) https://webapp.agron.ksu.edu/agr_social/article_new/in-season-palmer-amaranth-control-in-grain-sorghum-399-3
6. Kumar V, Liu R (2020) New study evaluated different herbicide programs for Palmer amaranth control in postharvest wheat stubble (eUpdate: June 26, 2020) https://webapp.agron.ksu.edu/agr_social/article_new/new-study-evaluated-different-herbicide-programs-for-palmer-amaranth-control-in-post-harvest-wheat-stubble-395-3
7. Kumar V (2020) Kansas weed survey: Producers/ag professional input requested (eUpdate: June 12) https://webapp.agron.ksu.edu/agr_social/article_new/kansas-weed-survey-producers-ag-professionals-input-requested-393-9
8. Lancaster S, Dille A, Kumar V (2020) World of Weeds: Kochia (eUpdate: Jan 17) https://webapp.agron.ksu.edu/agr_social/article_new/world-of-weeds-kochia-369-1
9. Kumar V, Liu R, Peterson DE (2019) Management of feral rye with CoAXium wheat production system in Kansas (eUpdate: Oct 11, 2019) https://webapp.agron.ksu.edu/agr_social/article_new/management-of-feral-rye-with-coaxium-wheat-production-system-in-kansas-357
10. Kumar V, Currie RS, Stahlman PW (2018) Kochia accessions with cross-resistance to dicamba and fluroxypyr identified in western Kansas (eUpdate: Oct 5, 2018) https://webapp.agron.ksu.edu/agr_social/article_new/kochia-accessions-with-cross-resistance-to-dicamba-and-fluroxypyr-identified-in-western-kansas-301
11. Peterson DE, Kumar V (2018) CoAXium wheat and aggressor herbicide for grass weed control (eUpdate: Nov 9, 2018) https://webapp.agron.ksu.edu/agr_social/article_new/coaxium-wheat-and-aggressor-herbicide-for-grass-weed-control-307