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Weeds

Photo Credit: Jamie Street - Unsplash.com (Cropped from original)
Description:

Weeds are considered the #1 pest in agroecosystems. They compete with desirable plants and can reduce yields, and alter soil structure and quality. Weed management requires thoughtful planning and action. Use the resources below to help reduce the effect of weeds in your crop, garden, or landscape.

PNW Weed Management Handbook

By Ed Peachey

This comprehensive guide to weed management in the Pacific Northwest covers biological weed control agents; pesticide safety and disposal; agrichemicals and their properties; and control of problem weeds.

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Photo Credit: Jonne Huotari - Unsplash.com (Cropped from original)

Featured Resources

Malheur Experiment Station Virtual Field Tour - Controlling Glyphosate Resistant Weeds in Sugarbeets

Learn about an applied research project that is testing herbicides for the control of glyphosate resistant weeds in sugarbeets.

Christy Tanner, Joel Felix | Aug 2020 | Video Peer reviewed (Gray level)

Malheur Experiment Station Virtual Field Tour - Sonalan Tank Mixes for Weed Control in Potato

Learn about an applied research project evaluating tank mixes of the herbicide Sonalan for controlling weeds in potato.

Christy Tanner, Joel Felix | Aug 2020 | Video Peer reviewed (Gray level)

Onion Response to Talinor Herbicide - A Virtual Field Tour

A Malheur Experiment Station virtual field tour. Weed Scientist Joel Felix discusses a field trial evaluating the herbicide Talinor for use in onions.

Christy Tanner | Aug 2020 | Video Peer reviewed (Gray level)

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Having weed problems?

Solve Pest Problems is a partnership between OSU and Oregon stakeholders to provide a user-friendly online resource to help urban and rural property managers to solve pest problems. Learn research-based, safe, and effective tactics for common garden and property pests and weeds. We provide non-chemical methods alongside the most effective and least toxic chemical options available, to reduce risk to people and the environment.

Learn more

Common weeds

Pigweeds: Current and Emerging Weed Threats in the Pacific Northwest

Pigweed is an invasive plant pest usually found in disturbed areas, like farmland and along roadsides and fencelines. Because their aggressiveness can reduce crop yields, this PNW discusses how to prevent or curtail...

Albert Adjesiwor, Timothy S. Prather, Joel Felix | Nov 2021 | Extension Catalog publication Peer reviewed (Orange level)

Integrated Management of Prickly Lettuce in Wheat Production Systems

Prickly lettuce is a common weed in wheat production systems throughout the PNW, but it’s difficult to manage. Herbicides can control prickly lettuce in wheat, but many biotypes have developed resistance. An ...

Drew J. Lyon, Ian C. Burke | Feb 2021 | Extension Catalog publication Peer reviewed (Orange level)

Integrated Management of Downy Brome in Winter Wheat

Downy brome (Bromus tectorum L.), also known as cheatgrass, is especially troublesome in low precipitation production areas where crop rotations are mostly limited to winter wheat followed by a year of summer ...

Drew J. Lyon, Andy Hulting, Don W. Morishita, Frank Young | Aug 2020 | Extension Catalog publication Peer reviewed (Orange level)

Integrated Management of Feral Rye in Winter Wheat

Feral rye (Secale cereale L.), also known as volunteer rye, is a troublesome weed in winter wheat production in the low- and intermediate-rainfall zones of eastern Washington and Oregon and southern Idaho. This ...

Drew J. Lyon, Andy Hulting, Judit Barroso, Joan Campbell | Jun 2020 | Extension Catalog publication Peer reviewed (Orange level)

Puncturevine

A member of the Caltrop family, this weed produces woody fruits that always land with one sharp spine pointed upward. Spines injure hooves, feet, and vehicle tires. A toxin from the plant may be linked to ...

Robert (Bob) Parker, Rick Boydston, PhD | Apr 2020 | Extension Catalog publication Peer reviewed (Orange level)

More common weed guides

Best Management Practices for Managing Herbicide Resistance

By Drew J. Lyon, Judit Barroso, Joan Campbell, Doug Finkelnburg and Ian C. Burke

Learn to manage herbicide-resistant weeds on your farm using the most effective methods, also known as best management practices (BMPs).

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Photo Credit: Marcel Poncu - Adobe Stock (Cropped from original)

Latest Resources

Field crop plant health challenges

This collection offers a thorough examination of the hurdles that plants confront, highlighting a varied group of challenges in agricultural and natural environments. Explore the fundamentals of plant health by delving into topics ...

Mary Corp | Jan 2024 | Collection

Douglas County noxious weed policy and noxious weed list

“Noxious Weed” is a legal definition for non-native plants that are particularly aggressive, invasive and difficult to control. The Douglas County Noxious Weed Advisory Board maintains a website with this weed list information.

Jan 2024 | Online resource

Is vinegar effective for killing weeds?

Q: What do you recommend for keeping weeds at bay in planting beds? We'd like to stop using Round-Up. Our beds are too big and the weeds are too numerous to be able to keep up mechanically. Would a vinegar solution be harmful to the soil?

A: View answer | View all featured questions

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Latest News

Living on the Land supports small-acreage landowners in the south Willamette Valley

OSU Extension collaborates with Oregon’s Soil and Water Conservation Districts and watershed councils to develop the series to best address natural resources concerns in the local area.

Melissa Fery | Apr 2024 | Impact story

Extension equips Baker County land managers to face the challenge of invasive and noxious weeds

A post-workshop evaluation found that 100% of respondents indicated that they planned to incorporate at least one item from the workshop into their management actions.

Will Price | Mar 2024 | Impact story

Solve Pest and Weed Problems website gives gardeners solutions

The content – peer reviewed by the OSU Department of Horticulture – is presented in categories with information below each photo. Clicking on the photo takes users to another page that offers information about identification, ...

Signe Danler | Mar 2023 | Impact story

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Meet Our Experts

Judit Barroso
Weed Science
Marcelo Moretti
Assistant Professor

Contact me with questions about weed management in commercial agriculture.

Cassie Bouska
Cassie Bouska
Agriculture

Contact with me with questions about agriculture in Coos and Curry counties

headshot of Brooke Edmunds
Brooke Edmunds
Community Horticulture, Master Gardeners

Contact me about the Master Gardener Program or gardening questions from Marion or Polk counties

See All Weeds Experts
Ask Extension

Have a question? Ask Extension!

Ask Extension is a way for you to get answers from the Oregon State University Extension Service. We have experts in family and health, community development, food and agriculture, coastal issues, forestry, programs for young people, and gardening.

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Is vinegar effective for killing weeds?

Q: What do you recommend for keeping weeds at bay in planting beds? We'd like to stop using Round-Up. Our beds are too big and the weeds are too numerous to be able to keep up mechanically. Would a vinegar solution be harmful to the soil?

A: View answer | View all featured questions

See More Questions