1. Topics
  2. Pests, weeds and diseases

Invasive species

Photo Credit: Emilio100 - Adobe Stock (Cropped from original)
Description:

OSU Extension helps Oregonians identify, report and manage invasive species that threaten ecosystems, agriculture and communities. We provide science-based tools, educational resources and collaborative programs to prevent the introduction and spread of harmful plants, animals and pathogens.

Latest Resources

Bristly hawksbeard ID guide

Bristly hawksbeard is a common weed in Western Oregon and Washington. The fast-growing annual bears bright yellow flowers. Stems have fine, soft hairs.

Renan N.D. Favera, Carol Mallory-Smith, Victor Hugo Vidal Ribeiro | Dec 2025 | OSU Extension Catalog Peer reviewed (Orange level)

How to get rid of tree-of-heaven: Solve Pest Problems

Tree-of-heaven is an invasive tree that spreads quickly and is difficult to control. It is a preferred food source for the invasive insect species spotted lanternfly. Learn how to identify and take action to control this aggressive weed.

Weston Miller, Jessica Green, J. Jeremiah Mann | May 2025 | Online resource

Spotted lanternfly resources

Spotted lanternfly (SLF) poses a threat to tree fruit and grape production. SLF has been reported as a serious pest in its invaded and home ranges.

May 2025 | Collection

Browse All Resources

Controlling Invasive Plants

Some common garden plants have become invasive pests in wild habitats. In Oregon, these invasives include some favorites such as English ivy and butterfly bush.

View collection
Photo Credit: yvonne navalaney - Adobe Stock (Cropped from original)

Invasive Insects

Emerald ash borer resources

Learn how to identify ash trees and the emerald ash borer beetle. Find out how Oregonians are working to prevent the spread of this destructive insect.

Aug 2022 | Collection

Brown marmorated stink bug (BMSB)

Information and resources about the brown marmorated stink bug (BMSB), an invasive

Nik Wiman, Rick Hilton, Clive Kaiser, Vaughn Walton, Rachel Suits, David Lowenstein, Victoria Skillman, Heather Andrews | Dec 2018 | Collection

Spotted Wing Drosophila (SWD)

Information and resources about monitoring, identification, and management of spotted wing drosophila (SWD), an invasive fruit fly.

Vaughn Walton, Linda Brewer, Bernadine Strik, Patricia A. Skinkis, Peter Shearer, Jana Lee, Man-Yeon Choi | Apr 2024 | Collection

Northern giant hornet resources

Information from the Washington State Department of Agriculture about the Northern giant hornet (formerly Asian giant hornet).

Oregon Master Beekeeper Program

Bronze Birch Borer

Information on the bronze birch borer from the Pacific Northwest Pest Management Handbook.

Jul 2018 | Online resource

Spotted lanternfly resources

Spotted lanternfly (SLF) poses a threat to tree fruit and grape production. SLF has been reported as a serious pest in its invaded and home ranges.

May 2025 | Collection

Become an Oregon Forest Pest Detector!

Oregon Forest Pest Detectors (OFPDs) are trained to recognize the signs and symptoms of invasive forest insects. They apply these skills in their day-to-day activities as arborists, parks managers, foresters, community tree stewards, Master Gardeners and other roles.

Learn more

Aquatic Invasive Species

Zebra & Quagga Mussels Species Guide

This guide provides in depth information on invasive zebra and quagga muscles. It is a companion resource to the Menace to the West an invasive species curriculum. Appropriate for grades 8-12.

Samuel Chan, Tania Siemens, Rick Cooper | Mar 2021 | Online resource

Pest alert: Invasive zebra mussels arrive in Oregon in "moss" balls sold for aquariums

Pest alert! The highly invasive Zebra mussel has made it into Oregon through moss balls, popular among aquarium hobbyists and commonly sold in pet stores. Invasive species experts say potentially contaminated moss balls should be destroyed.

Adriene Koett-Cronn, Samuel Chan | Mar 2025 | OSU Extension Catalog Peer reviewed (Gray level)

Latest News

Volunteers collect Oregon ash seeds to fight EAB

Trained volunteers and youths gather seeds statewide to preserve Oregon ash before emerald ash borer spreads.

Dan Stark | Mar 2026 | Impact story

Emerald ash borer in Oregon: what to do now — and what to plant next

Don’t remove healthy ash preemptively, learn the symptoms and start planning resilient replacements.

Kym Pokorny | Sep 23, 2025 | News story

Oregon State researchers develop forecast model for spotted lanternfly

The forecasts provide surveillance support, targeted control, and highlight regions at high risk of establishment.

Leonard Coop | Sep 2025 | Impact story

All News

Explore more resources

Upcoming Events

Mar 18

Plant This, Not That*

12:00 pm - 1:00 pm PDT Online
May 9

Spring Weed Watchers Workshop

10:30 am - 12:00 pm Corvallis, OR
See All Events

Meet Our Experts

Samuel Chan
Extension Specialist in Watersheds & Aquatic Invasive Species
Silvia I. Rondon
Director of Oregon IPM Center

Contact for Integrated Pest Management questions

Photo of Lorelle in the woods on a trail.
Lorelle Sherman
Forestry and Natural Resources Extension Forester, Assistant Professor (Practice)
Dan Stark selfie
Dan Stark
Forestry and Natural Resources, Assistant Professor of Practice
See All Invasive species 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.

Ask us a question

Should I prune my ash trees now to help prevent an emerald ash borer infestation?

Q: I live in Beaverton and I want to prune my two large ash trees before the fall winds come. I think emerald ash borers would find the sap from my pruned trees attractive. When is it safe to prune my ash trees?

A: View answer | View all featured questions

See More Questions