War Against Weeds

In the last episode of season 11, Sarah and Alyssa sit down with Dr. James Leary to explore the innovative world of herbicide ballistic technology. James shares how his work in Hawaii led to the development of herbicide-filled projectiles designed to target invasive plants in hard-to-reach terrain. The conversation dives into the science, logistics, and surprising practicality of "shooting weeds," and how creative thinking can transform invasive species management and conservation efforts.   Here are some resources our guest shared! https://www.youtube.com/watch?v=988i6SQKSzY https://www.youtube.com/watch?v=tWYR6C3T3NQ   Transcript: PDF: https://app.box.com/s/a2cicz0jpo74m02otm8bjhkmcngjjns7 DOC: https://app.box.com/s/ekzn3mq1jwi0hlq449qz5a49ip7ilmes  

In this episode of War Against Weeds, the hosts sit down with weed science experts Dr. Peter Dotray (Texas Tech University) and Dr. Stanley Culpepper (University of Georgia) to explore the unique challenges of growing cotton across different regions of the U.S. From starting clean at planting to the critical role of timely herbicide applications and overlapping residuals, they break down what it takes to manage weeds in this slow-growing, high-maintenance crop.   Episode Trancript PDF: https://app.box.com/s/up693ucumuokzjoz6su63t43rb72n6io DOC: https://app.box.com/s/2ee7afg6rki1qegpowitnncgs69v1l7e  

This week Joe Ikley and Sarah Ganske are joined by Dr. Tom Mueller (University of Tennessee) to discuss sprayer hose cleanout and herbicide residue risks. The conversation focuses on how hose materials, aging, and system design affect herbicide retention, with research insights comparing dicamba and 2,4-D cleanout challenges. They also share practical recommendations for applicators, including agitation practices, downtime risks, and when hose replacement may be necessary to avoid crop injury.   Link: https://utcrops.com/   Transcripts:  PDF: https://app.box.com/s/4esrl1zv0dd0za3uojxah0jpwvqdy90i DOC: https://app.box.com/s/frnfuvcvn5t7h6kg11v4cch4jmeigsny

In this episode of the War Against Weeds podcast, Alyssa Essman and Sarah Lancaster Ganske are joined by Purdue Extension weed scientist Dr. Tommy Butts for a deep dive into spray nozzles, droplet size, and deposition. The conversation covers how nozzle selection influences coverage, drift, deposition, and weed control, with practical recommendations for ground applications, pulse sprayers, and managing risk in real-world conditions.    Epsisode Transcript PDF: https://app.box.com/s/rci0uzr4ww772196tdfeia0vvrdidzas DOC: https://app.box.com/s/398aewwxuygy3rrf3d968e5iyae6vqc4

In this episode of the War Against Weeds podcast, Sarah and Joe welcome Dr. Katie Dentzman of Iowa State University to explore the human and social dimensions of herbicide resistance management. The conversation digs into why "silver bullet" solutions are so appealing, the real-world barriers to adopting integrated weed management, and how community dynamics shape decision-making in agriculture. Episode Transcript PDF: https://app.box.com/s/jttzmn1oq5mxq4n629j7ieo16l1muf7p DOC: https://app.box.com/s/ek68ebp2ztqu8lsh7msn82427fvavio8

In this episode Sarah and Joe welcome Hudson Takano of Corteva Agriscience for an update on the Herbicide Resistance Action Committee (HRAC) and the newly released 2026 HRAC Mode of Action poster. Hudson explains HRAC's role in resistance management, how herbicides are evaluated and classified, and what goes into updating the poster. The conversation highlights newly added herbicides, and why some older or low-use herbicides were removed. The episode also looks ahead to future HRAC work, upcoming herbicides, and where listeners can find the latest HRAC resources online.   https://hracglobal.com/tools/2026-hrac-global-herbicide-moa-classification   Episode Transcript PDF: https://app.box.com/s/i7fb437reya4ipjf8fbwqagw03jq2c6a DOC: https://app.box.com/s/ur49aaooemdaqlswqfnmu15o5frly1e8

In this episode of the War Against Weeds podcast, Sarah Ganske and Joe Ikley explore the emergence of PPO resistant kochia across the northern Great Plains. Joined by BASF scientists Dr. Ingo Meiners and Dr. Aimone Porri, the group walks through how field failures led to greenhouse confirmation and the discovery of novel PPO target‑site mutations. They discuss why these mutations affect some PPO herbicides but not others and how the findings are already shaping resistance diagnostics and management decisions. They end the episode with practical guidance for growers and a broader look at the importance of collaboration in tackling evolving weed resistance challenges. Transcripts PDF: https://app.box.com/s/619xibmb42kh782frwg7ul8yhmtl289c DOC: https://app.box.com/s/xwwkr88cmm9jc59ihjtqbxvic7f1x5y9

In this episode of War Against Weeds, hosts Alyssa and Sarah sit down with Dr. Karla Gage (Southern Illinois University Carbondale) and Dr. Pat Tranel (University of Illinois) to discuss emerging glufosinate resistance in waterhemp and what it means for growers moving forward. Transcripts PDF: https://app.box.com/s/0lyejemx8kyjr8s1fcgca6huqw3qaprp WORD: https://app.box.com/s/la2r3yx4208jm2v8khac9wf8zm5glfab

In this episode of War Against Weeds, Joe Ikley and Alyssa Essman talk with spray technology experts Dr. Tom Wolf and Dr. Jason Deveau about how rapidly spray drones have evolved and why they're challenging to use effectively. They discuss issues like swath variability, droplet behavior, and operator exposure, while also highlighting situations where drones offer clear logistical advantages. The result is a candid, practical look at both the promise and limitations of agricultural spray drones today.

In this episode of War Against Weeds, Sarah and Alyssa sit down with Dr. Reid Smeda of the University of Missouri to dig into the biology, history, and management of invasive teasels. From their origins to their modern spread along roadsides, teasels prove to be more troublesome than their quirky seed heads suggest. Dr. Smeda breaks down why they're so difficult to control and shares long‑term strategies for effective management in rights‑of‑way and beyond. Whether you've seen teasel creeping into your county or just want to stay ahead of emerging noxious weeds, this is a conversation you won't want to miss.   Episode Transcripts PDF: https://app.box.com/s/sn8ypb72g1scf0xxvv1zgkb6916t6p77 DOC: https://app.box.com/s/cli6p5ld0vlemyq0m642y2osk049biof     Teasel resources https://www.fs.usda.gov/database/feis/plants/forb/dipspp/all.html https://mdc.mo.gov/trees-plants/invasive-plants/common-cut-leaved-teasel-control https://www.purdue.edu/fnr/extension/wp-content/uploads/2025/04/FNR-649TeaselADA-final-comp.pdf https://www.nps.gov/articles/cutleaf-teasel.htm https://www.dnr.state.mn.us/invasives/terrestrialplants/cutleavedteasel.html   Bentivegna and Smeda https://doi.org/10.1614/IPSM-D-10-00026.1 https://doi.org/10.1614/WT-08-043.1    

In this episode, Joe and Alyssa talk crabgrass with Purdue's Dr. Aaron Patton and PhD candidate Vera Vuković, covering why smooth crabgrass dominates lawns, how mowing height and fertility can dramatically reduce infestations, and what new research reveals about seed dormancy, germination cues, and emergence timing. They break down practical pre‑ and post‑emergence control strategies—including phenology-based timing and herbicide options—while also touching on emerging issues like quinclorac resistance.   https://edustore.purdue.edu/turf-100.html   https://turf.purdue.edu/turfgrass-weeds/   Aaron Patton on X: @PurdueTurfDoc   Episode Transcripts PDF: https://app.box.com/s/mxdmzk8izjtsben1uin2nq4kyv2b0nz7   DOC: https://app.box.com/s/vimx2nv9cl3vsv3rlaj417pg7uipvrum  

Annual ryegrass is rapidly becoming one of the toughest weeds in U.S. row‑crop agriculture. In this episode, Alyssa Essman (Ohio State) and Joe Ikley (NDSU) talk with Tom Barber (University of Arkansas), Charlie Cahoon (NC State), and Larry Steckel (University of Tennessee) about how this weed is spreading, shifting its emergence timing, and developing resistance to multiple herbicide groups. The guests discuss the strengths and weaknesses of current control options, the importance of fall residuals, and how tactics like tillage, cover crops, and harvest weed‑seed control fit into an integrated approach. They also share ongoing research aimed at better understanding ryegrass biology and improving long‑term management.   https://crop-soil-environmental-sciences.uark.edu/people/faculty-directory/uid/ltbarber/name/Tom+Barber/ [crop-soil-...s.uark.edu] https://cals.ncsu.edu/crop-and-soil-sciences/people/cwcahoon/ [cals.ncsu.edu] https://utcrops.com/field-crops-team/ [utcrops.com]

In this episode of War Against Weeds, Sarah and Joe sit down with Dr. Jane Mangold of Montana State University to unpack the ecology, spread, and management of cheatgrass and other invasive grasses. Jane explains why species like cheatgrass and ventenata are thriving in the Western U.S., how fire and climate patterns influence their behavior, and what tools land managers can use to stay ahead of infestations. The conversation covers biology, prevention, grazing, herbicide strategies, and new resources available to support rangeland health.   https://www.invasivegrasses.com/

In this episode of War Against Weeds, hosts Alyssa Essman and Joe Ikley sit down with Melissa Widhalm, Associate Director and Regional Climatologist at the Midwestern Regional Climate Center (MRCC). Melissa introduces WEST — the Weed Emergence Scouting Tool — an experimental, temperature‑based system designed to predict first and peak emergence of key weeds like giant ragweed and waterhemp across the Midwest.

In this episode Alyssa Essman and Sarah Lancaster sit down with Washington State University toxicologist Dr. Allan Felsot for a crash course in Toxicology 101. Dr. Felsot breaks down how the EPA evaluates pesticide safety, explains the difference between hazard and risk, and clarifies common misconceptions about chemical exposure, tolerance, and persistence. The conversation also touches on glyphosate, PFAS-related concerns, and why effective science communication—and early education—matter for helping the public understand pesticide technology.

Season 11 opens with Dr. Brad Hanson of UC Davis, who joins Joe and Alyssa to unravel the resurgence of broomrape, a challenging parasitic weed threatening California's tomato processing industry. Brad explains how broomrape's underground lifecycle, tiny long-lived seeds, and strict reliance on host plants make it difficult to detect and manage. The episode covers the difference between broomrape species appearing in North America, why processing tomatoes are especially vulnerable, and how broomrape spreads through equipment and soil movement.   Here are some sources Dr. Hanson shared for the listeners:  UC broomrape page (in progress) https://broomrape.sf.ucdavis.edu/ California Tomato Research Institute's broomrape resource page (mostly UC extension info) https://tomatonet.org/grower-resources/broomrape-resources/ California Department of Food and Agriculture broomrape program page https://www.cdfa.ca.gov/plant/ipc/broomrape/ This is a video article that the UCD college of ag put together a couple years ago https://caes.ucdavis.edu/news/parasitic-weeds-threaten-tomato-plants-california-farms

On our last episode of season 10, all three hosts have a discussion on the future of weed science with Dr. Larry Steckel (University of Tennessee) and Dr. Aaron Hager (University of Illinois). They reflect on the evolution of weed management, including the increase of specific weed species, and the challenges of herbicide resistance. Both emphasize the need for integrated approaches, including cover crops, precision technology, and cultural practices.

Joe Ikley and Sarah Lancaster discuss the North Dakota Agricultural Weather Network (NDAWN) and the Kansas Mesonet with directors Daryl Ritchison and Chip Redmond, respectively. NDAWN, with over 250 stations, provides high-resolution weather data, including soil moisture and temperature measurements. Kansas Mesonet, with 94 stations, focuses on real-time data for agricultural and emergency management purposes. Both networks emphasize the importance of accurate weather data for herbicide application, particularly wind speed, inversions, and delta T measurements. The conversation highlights the critical role of Mesonets in agriculture and emergency response.

Sarah and Alyssa sit down with dryland experts Jeanne Faulk Jones (Kansas State University) and Dr. Drew Lyon (Washington State University). They highlight the challenges of managing weeds in semi-arid regions, including key weeds like Palmer amaranth, Kochia, and perennial grasses. They also discuss various strategies for water conservation and weed management.   Smallgrains.wsu.edu Facebook page: K state sunflower district agronomy X: cropswithgenie

Dr. Jason Norsworthy from the University of Arkansas sits down with Alyssa and Sarah to discuss the United Soybean Board's weed management project. This project involves screening for resistance to our most used herbicides in our most problematic pigweed species.

This week Alyssa and Joe chat with Dr. Jason Bond (Mississippi State University) all about redvine! This week's episode is also a crossover episode with The Mississippi Crop situation Podcast, so check them out here! https://extension.msstate.edu/shows/mississippi-crop-situation

Alyssa Essman and Sarah Lancaster sit down with Dr. Aaron Hager (University of Illinois) and Ryan Henry (UPL) to discuss Group 5 herbicides. They cover the historical use and mechanisms of these herbicides, as well as degradation, metribuzin rates, and new herbicides to the market.    Paper mentioned in the episode: Optimizing metribuzin rates for herbicide-resistant Amaranthus weed control in soybean link: https://www.cambridge.org/core/journals/weed-technology/article/optimizing-metribuzin-rates-for-herbicideresistant-amaranthus-weed-control-in-soybean/ECF728739388A3DB5BA2290B1105A385

Joe & Sarah sit down with Scott Cully and Dean Grossnickle to discuss herbicide premixtures. Scott, a senior field research biology expert, highlights his role in developing products like Acuron and Storen. Dean, a technical development lead, explains his commercial perspective. They detail the development process, including formulation challenges and the importance of proper adjuvant selection. They emphasize the need for accurate application to avoid issues and the benefits of pre-mixtures for ease of use and consistent results.

Sarah & Joe sit down with Dr. Eric Patterson from Michigan State University to chat about the The HERMON (Herbicide Resistance Monitoring Network) project. This project aims to create a network of researchers to develop and share new resistance tests and management strategies. The project includes 10 states and focuses on key herbicides like glyphosate, PPO inhibitors, and dicamba.   Link mentioned in the episode:  https://www.seedworld.com/us/2025/06/19/a-unified-front-on-weed-resistance/

This week Sarah and Alyssa chat with Dr. Todd Gaines from Colorado State University. They discuss the role of cytochrome P450 enzymes in herbicide metabolism and resistance. Dr. Gaines mentions ongoing research to understand the regulation of these enzymes and the potential for using gene editing to combat resistance. They also touched on the impact of stress on P450 activity and the development of new herbicides.    Here is the article mentioned in the episode: https://onlinelibrary.wiley.com/doi/full/10.1002/pld3.70102

This week on the War Against Weeds Podcast, Sarah and Alyssa chat with Dr. Allan Fritz, a professor in wheat breeding at Kansas State University! They discuss potential outcrossing between wheat and its wild relatives, particularly jointed goatgrass. The conversation touches on the potential for transgenic wheat and the regulatory challenges posed by consumer acceptance and market concerns. Link from the episode: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://wsweedscience.org/wp-content/uploads/OP5Carol.pdf

This week Sarah and Joe talk about canola production with Drs. Breanne Tidemann and Mike Cowbrough. They discuss the origins of canola, winter vs spring cultivars, and the challenges associated with growing canola.

This week Alyssa and Joe chat with Office of the Indiana State Chemist Jessica McVay and Scottie Pouliot about cover crop contamination in seed lots, and all the work they do behind the scenes.

This week Sarah and Joe chat with Drs. Kelsey Andersen Onofre (Kansas State University) and Andrew Friskop (North Dakota State University) about volunteer cereals and green bridges, specifically covering wheat streak mosaic virus.   You can find both of our guests here on X: @KSUWheatDisease and @NDSUcerealpath

Welcome back to the War Against Weeds Podcast for our season 10 premiere! We have Dave Thiessen on today to talk about combine settings during harvest. Dave emphasizes the importance of combine setup, including optimizing corn heads, deck plates, and rotor speeds to minimize harvest losses. They discuss the impact of weather, crop conditions, and machine maintenance including regular power shutdowns to minimize volunteer crops the following season. 

This week we have Ngaio Richards, Amber Burch, and Josh Wagoner on to talk about how the Early Detection, Rapid Response Program in collaboration with the Working Dogs for Conservation utilizes dogs to find noxious weeds. They talk about their work in controlling Dyer's Woad in Montana, as well as other noxious weeds that the dogs are trained to identify.   Our guests provided some really great resources for anyone who might be interested, as well as the gear they use for protecting their dogs in the field. https://wd4c.org/ https://outfoxfordogs.com/?srsltid=AfmBOoqp6TYSdqp7PEZGM-vYndGKwt5W1W-PHpExvhYuHjQaHCqhzNoL https://agr.mt.gov/Noxious-Weed-Task-Force-Program#:~:text=The%20Early%20Detection%2C%20Rapid%20Response,of%20efforts%20across%20the%20state

This week on the War Against Weeds Podcast we have two guests on to talk about L-glufosinate. They talk about the Liberty Ultra label and how the ESA (Endangered Species Act) has influenced this new label. Our guests are Liam Vincent a technical marketing manager for BASF, and Lynn Justesen a technical services lead with UPL.

This week we have Dean Riechers from Univeristy of Illinois joining the podcast to talk about herbicide sites of action.        Title of mentioned publication:  Herbicide resistance is complex: a global review of cross-resistance in weeds within herbicide groups Link our guest wanted to share: https://riecherslab.cropsciences.illinois.edu

We are joined by Rodrigo Werle and Andy Bensend this week to talk about Non-GMO Soybeans!   A few links our guests wanted to share with listeners: https://unitedsoybean.org/about-the-checkoff/ https://wiscweeds.info/ https://coolbean.info/ https://wisoybean.org/   You can find Rodrigo on X @WiscWeeds  

This week we have Dan Beran and Bob Bruss on to talk about dichlorprop-p. They cover the history and potential future of this active ingredient. Listen now! To find more information about Nufarm go here: https://nufarm.com/uscrop/

This week Alyssa and Sarah chat with Caleb Wepprecht and Aaron Hager with University of Illinois about using fertilizers as carriers for herbicide applications.

This week on the War Against Weeds Podcast we have Dr. Andy Robinson on to chat about all things potatoes. He covers weed management, planting, harvesting and where you can find most of our potato production here in the states!

It's a bird... it's a plane... it's drones!! Join us this week as Alyssa and Joe discuss all things drones with Dr. Steve Li. If you or anyone you know is interested in drones for agricultural use, consider attending the 2025 Spray Drone End User Conference.   For more info on the conference: https://www.aces.edu/blog/topics/farming/2025-spray-drone-end-user-conference/

This week we have Dr. JD Green on the podcast to cover everything Johnsongrass. He covers the history of Johnsongrass and how to manage it. Available now!

This week we have Dr. Michael Walsh with Charles Sturt University on the podcast to talk about the "weed chipper". The weed chipper is a mechanical weeding implement that could be an answer to herbicide resistant weeds. Listen now to find out how the weed chipper works!   To see the weed chipper in action: https://www.youtube.com/watch?v=-1nI6Gh9khI

This week Sarah and Joe chat with Dr. Bill Johnson from Purdue University about henbit. They cover why controlling henbit is important and how to manage it in corn and soybean production. Listen now!

This week our host Sarah and co-host Joe chat with Dr. Erin Burns (Michigan State University) and Dr. Dan Quinn (Purdue University) about short corn. What makes it different from standard corn? What does weed control look like? Listen to find out!   Erin's Links: https://www.canr.msu.edu/weeds/   Dan's Links: https://ag.purdue.edu/department/agry/faculty-pages/the-kernel/ X: @PurdueCorn https://www.hoosieragtoday.com/podcast/purdue-crop-chat/

Welcome back to the War Against Weeds Podcast! This week we are joined by guests Kevin Bradley (University of Missouri) and Dwight Lingenfelter (Penn State University) to discuss weed management in pasture systems. They cover the different weeds found in pastures, non-chemical methods, and the importance of fertility.   Kevin's Links: https://weedscience.missouri.edu/ https://www.facebook.com/weedscience.missouri X: @ShowMeWeeds   Dwight's Links: General Weed ID references: Weeds of the Northeast (2nd ed. 2023) - great reference >500 weed species with images and descriptions Newcomb's Wildflower Guide (or similar others) Toxic plant databases and info: University of Wisconsin Poisonous Plants of Concern to Wisconsin's Livestock Canadian Poisonous Plants Information System Colorado Guide to Poisonous Plants Cornell Plants Poisonous to Livestock database University of Illinois School of Vet Medicine Poisonous Plants database USDA Poisonous Plant Research Laboratory (Logan, Utah) and ARS Bulletin 415 Plants Poisonous to Livestock in the Western USA  

This week on the War Against Weeds Podcast, we have special guest Dr. Tom Wolf joining us to talk about water quality and its impact on herbicide applications.    You can find Tom on X: @nozzle_guy   Additional helpful links: https://sprayers101.com/mode-of-action-and-spray-quality/ 2025 ND Weed Guide: https://www.ndsu.edu/agriculture/sites/default/files/2024-12/2025%20ND%20Weed%20Guide%20Final_With%20Color%20Covers.pdf

Welcome back to season 9 of War Against Weeds! We are so excited to be back, and to start our season off with Roger Batts to discuss his work with the IR-4 Project. Learn about what IR-4 is and what services it provides for farmers across the United States.

For our final episode of season 8, we have agronomists Kyle Okke, Jason Hanson and Jeff Nagel on to discuss the economics of weed control for growers. They cover their major weed challenges and how additional inputs like machinery cost, fertility, and pest management are all factored into planning for '25. Let's wrap up this season by reflecting on '24, and looking into '25!   You can find Jason and Kyle on X at: @rocknrollagrnmy and @okkefromuskogee And find their podcast Agronomists Happy Hour at https://agronomistshappyhour.com/ And on X @AgHappyHour   You can find more information about Keystone Cooperative here: https://www.keystonecoop.com/   Thank you all for another great season!

Dr. Todd Gaines with Colorado State University joins us this week to talk about some novel genetic methods to control weeds! He covers the genomic timeline and how things have changed through the years, and  how genomics helps understand herbicide resistance by identifying target site genes and mutations.    Some links that Dr. Gaines wanted to share: https://www.weedgenomics.org/ https://link.springer.com/article/10.1186/s13059-024-03274-y https://www.ingentaconnect.com/content/resinf/opm/2024/00000035/00000004/art00002

Welcome back to the War Against Weeds Podcast! This week we are joined by guests Jeremy Safranski (Director of Strategic Planning at CHS Inc.) and Mike Bjertness (Management at C-W Valley Co-op) to discuss the herbicide supply chain and their experiences in the United States.  You can find these two guests here: https://www.linkedin.com/in/mike-bjertness-cca-0b404326a/ https://www.linkedin.com/in/jeremy-safranski0312/   And the links they provided for more information: www.cwvalley.com www.chsinc.com

This week on the War Against Weeds Podcast, we have special guests Drs. Cara McCauley and Jason Adams on to chat about the herbicide discovery process. They cover the many things involved in creating new chemistries for farmers to use in the war against weeds!   If you want to reach out to either of our guests, you can find them here: https://www.linkedin.com/in/cara-mccauley/ https://www.linkedin.com/in/jason-adams-6b356322b/   Thanks for listening!

This week on the War Against Weeds Podcast, we have Drs. Dale Shaner and Tom Mueller joining us to discuss enhanced degradation of triazine herbicides!   You can find more information on this topic at these links below provided by our guests. https://utia.tennessee.edu/publications/wp-content/uploads/sites/269/2023/10/PB1580.pdf https://utcrops.com/ https://scijournals.onlinelibrary.wiley.com/doi/abs/10.1002/ps.1909   Thanks for listening!