Weeders of the West

Recent research conducted at Oregon State University confirms that certain wild carrot populations in Oregon are now resistant to flazasulfuron. This is the first confirmed case of flazasulfuron resistance in wild carrot, and it carries important implications for hazelnut growers across the Pacific Northwest.

University of Idaho's Doug Finkelnburg shares how this anomalous warm winter weather affects weed and crop growth in 2026.

Oregon State University's Aaron Becerra-Alvarez conducted a study to see if different adjuvants could improve the spectrum of control of HPPD-inhibitors when applied in POST. This could give producers flexibility for fall cover crop planting or crop rotations by avoiding use of other herbicides with longer soil carryover.

Contributed by Albert Adjesiwor and Sushmita Sharma, University of IdahoIntroduction to a weed that needs no introduction Wild oats (Avena fatua)--they’re fast, sneaky, and persistent. If you’re a small grain grower, you probably already know…

Oregon State University's Victor Ribeiro and David Maliszewski conducted a field study to determine if Talinor is effective at controlling Sharppoint fluvellin. They found that Talinor does not provide effective control. However, their observations suggest that Huskie can offer some control shortly after application, and additional management strategies, including follow-up treatments or herbicides with residual activity, may achieve extended control of Sharppoint fluvellin.

Oregon State University's Judit Barroso conducted some postharvest experiments to learn how to optimize the use of green-on-brown precision sprayers.

Washington State University's Dr. Drew Lyon reflects on weed science advancements through the last four decades and nods to his excitement about the future of the discipline.

Researchers from Oregon State University, Michigan State University, and Colorado State University discovered that annual bluegrass has become the first weed in the world to evolve resistance to indaziflam. This finding has major implications.

A recent survey by the Pacific Northwest Herbicide Resistance Initiative (PNWHRI) highlights how much weed pressure and complexity have grown over the past decade from the perspective of producers.

Oregon State University researchers have been exploring the potential of electric weed control (EWC) and are now investigating whether EWC could also be used to terminate cover crops—a vital component in organic vegetable farming. Their preliminary results are promising.

Oregon State University's Victor Ribeiro shares the results of an experiment to determine whether an Italian ryegrass population in the Willamette Valley was herbicide resistant. He also shares herbicide resistance management and control strategies.

To help with downy brome management, in 2022, Oregon State University's Judit Barroso initiated an experiment at the Columbia Basin Agricultural Research Center to study how cultural practices at seeding time might alleviate the problem. The results were surprising.

Washington State University's Drew Lyon discusses herbicide research about controlling smooth scouringrush in no-till systems conducted over the last decade. The research has informed new insights, but many questions remain for this perennial plant that has survived for millions of years.

In recent years, hazelnut growers and crop consultants in the Willamette Valley have reported declining herbicide performance despite the use of full recommended label rates and proper application timings. These observations raised concerns about potential herbicide resistance. Oregon State University researchers investigated this issue.

University of Idaho's Doug Finkelnburg shares research on the productivity of different annual forages in northern Idaho and their observations for successfully using forage crops as a weed management tool.

The Pacific Northwest Weed Handbook, a staple resource for weed management practitioners in the states of Oregon, Idaho, and Washington, is now available online. The handbook is designed as a quick and ready reference for weed control practices and herbicides used in various cropping systems or sites in the Pacific Northwest (PNW).

University of Idaho's Albert Adjesiwor and Chandra Montgomery got some fascinating results from a field study looking at crop rotations and three herbicide treatments: nontreated check, postemergence (POST) only, and preemergence (PRE) + POST herbicide.

Oregon State University's Victor Ribeiro summarizes the results of a weed management needs assessment survey conducted to identify the key challenges and priorities of Oregon growers and other agricultural stakeholders.

Intercrops can compete with weeds in the interrow reducing the establishment and survival of weeds. Oregon State University researchers conducted an experiment where winter wheat was intercropped with various legumes. Here are the results.

Washington State University's Dr. Drew Lyon discusses non-target-site resistance, a new form of herbicide resistance that has been identified in recent years.

Oregon State University's Marcelo L. Moretti shares best practices for using glufosinate to manage hop shoots and weeds in the growing season.

Oregon State University's Joel Felix shares the results of the IR-4 Project to evaluate the suitability of pyraflufen-ethyl to manage weeds in onion.

University of Idaho's Doug Finkelnburg, gives an update about the happenings with the Pacific Northwest Herbicide Resistance Initiative (PNWHRI) from new personnel and equipment to weed seed bank sampling to herbicide resistance mapping.

Oregon State University researchers report on the potential for robotic weed control after testing the FarmDroid FD20.

University of Idaho's Albert Adjesiwor does some research into how accurate various AI chatbots are for agricultural recommendations. The results may surprise you.