Concerned land managers are already seeing toxic Tansy ragwort blooming along roads and in fields. Its bright yellow flowers pop up throughout rural areas as well as urban yards and vacant lots. Even with landowners and volunteers working hard to remove it, everyone needs to control this weed. Although tansy ragwort is high on the list of plants that can harm animals, it is certainly not the only offender.
Toxic Plants: Protecting Horses and Livestock
Many toxic plants, known as “Pasture Bullies,” can be dangerous to horses and livestock. These plants include invasive weeds, native plants, and other plants that do not belong in pastures. Some can cause serious illness or even death if eaten.
The Clackamas Soil and Water Conservation District offers a handout about many of these harmful plants. The handout can help you identify toxic plants growing in your pasture or found in hay. Download the handout below for easy reference.
Download this Pasture Bullies handout below for easy reference.
The risk from toxic plants depends on how much of the plant an animal eats. The handout does not include every plant that may be harmful to horses or livestock. Instead, it focuses on plants commonly found in Western Oregon.
If you think an animal has eaten a poisonous plant, contact a veterinarian right away.
Tips to Prevent Poisoning
You can help prevent livestock poisoning by creating conditions that make it difficult for toxic plants to grow and spread. One key step is to reduce and control weeds. Consider using an Integrated Pest Management (IPM) plan to manage your land.
A key part of IPM is maintaining healthy pastures with strong soil and quality forage. Healthy grass can be a strong competitor against invasive weeds.
To improve pasture health:
- Allow pasture grass time to recover after grazing. Do not let animals graze grass shorter than three inches before moving them to another pasture.
- Divide your land into smaller paddocks and rotate animals between them. This gives grazed areas time to rest and regrow.
- Create a sacrifice area for use during the rainy season. This helps protect pasture soil and grass from damage caused by animal hooves on wet ground.
- Test your soil regularly. Based on test results, add manure, lime, or fertilizer as needed to improve soil health.
Additional Resources
- Protect Your Horses and Livestock From Toxic Plants – A guide to identifying and controlling common toxic weeds and other harmful plants. Produced by the Washington State Noxious Weed Control Board.
- Tips on Land and Water Management for Small Acreages in Oregon
- Managing Small-Acreage Horse Farms in Western Oregon and Western Washington by Melissa Fery, David Hannaway, Garry Stephenson, Linda J. Brewer, and Scott Duggan
Questions About Pasture Bullies or Pasture Management?
For more information about toxic plants or pasture management, contact the Clackamas Soil and Water Conservation District at 503-210-6000. Our Conservation Planners and WeedWise Specialists can help you protect your livestock and improve your pasture.