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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.

2022 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)

More resources

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 their spread ...

Joel Felix | Nov 2021 | OSU Extension Catalog 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 integrated management ...

Feb 2021 | OSU Extension Catalog 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 fallow. The invasive ...

Andy Hulting | Aug 2020 | OSU Extension Catalog 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 publication ...

Andy Hulting, Judit Barroso | Jun 2020 | OSU Extension Catalog 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 photosensitization ...

Robert (Bob) Parker | Apr 2020 | OSU Extension Catalog 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

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. 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.

Weston Miller | Oct 2022 | Online resource Peer reviewed (Gray level)

How to manage Tansy Ragwort?

Q: We have wheat planted and along our fence line we have an infestation of tansy ragwort. Is it a good time to cut the flowers off, bag them, and leave the plant; or should I spray it? The neighbor across the road has...

A: View answer | View all featured questions

How can I support the endangered Monarch butterfly?

Q: I recently read in the news that the Monarch Butterfly was added to the endangered species list. What can I plant in my garden to help the butterfly? I read that milkweed plants are their natural habitat. Yesterday I ...

A: View answer | View all featured questions

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Latest News

Farm managers gain knowledge in OSU Extension’s virtual Coffee Hours

The Coffee Hour conversations attracted 37-61 people each week, including farmers who manage over 34,500 acres and agronomists who make crop management recommendations on over 209,000 acres.

Christy Tanner | May 2022 | Impact story

Controlling perennial bindweed takes persistence

This invasive perennial makes itself at home by sinking roots as much as 9 feet into the soil and can stay as an unwanted guest for up to 20 years.

Kym Pokorny | Apr 1, 2022 | News story

As Russian thistle becomes resistant to glyphosate, OSU Extension weed scientist finds alternatives for wheat farmers

Russian thistle thrives in the dry climate of eastern Oregon and Washington and if left unchecked develops an extensive root system that competes with wheat for water and nutrients.

Kym Pokorny | Nov 2, 2021 | News story

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Upcoming Events

Jan 23 - Jan 24

Pesticide Recertification Class

8:00 am - 2:35 pm Central Point, OR
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Meet Our Experts

Ed Peachey
Associate Professor, Department of Horticulture (Retired)

Contact for questions on vegetable production: processed, fresh market, and seeds

Andy Hulting
Weed Control
Judit Barroso
Weed Science
Cassie Bouska
Cassie Bouska
Agriculture

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

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How to manage Tansy Ragwort?

Q: We have wheat planted and along our fence line we have an infestation of tansy ragwort. Is it a good time to cut the flowers off, bag them, and leave the plant; or should I spray it? The neighbor across the road has...

A: View answer | View all featured questions

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