New UW-Extension identification guide to toxic plants available

Wisconsin State Farmer

MADISON – While most plants are safe for livestock to consume, a few plant species can sicken or even kill animals if ingested. Recognizing poisonous plants and knowing proper livestock management are important steps in minimizing the potential for poisoning according to Mark Renz, University of Wisconsin-Extension weed scientist at UW-Madison.

“We often receive questions about toxic plants, the level of toxicity, and what animals they are toxic to,” Renz said. “In this new identification guide, we have close-up pictures of the plants for easy identification, and detailed information on the most common toxic plants in Midwestern pastures, as well as forage crops.”

In addition to identification information about plants, the guide provides detailed information on what the toxin is, what animal species it is toxic to, where the plant is generally found, what parts of the plant are toxic and how long the toxin persists, and what can be done.

The easy to use, spiral-bound book, Toxic Plants in Midwest Pastures and Forages, is available online at The Learning Store The guide can either be downloaded for free or a hard-copy purchased.

“Toxicity in plants is a complex issue as it can occur throughout the year depending on the plant and environmental conditions. Because of this we encourage landowners and animal owners to inform themselves on plant toxicity so they can make the correct management decision,” Renz warns. 

If you suspect plant poisoning in livestock, follow these recommendations:

  • Remove animals from where the plants are present and remove any affected feed or forage.
  • Contact your veterinarian.
  • Survey the area to identify any plants that may be the potential source of toxicity. Use a digital camera to compare the images to online identification databases such as or published references. You can also submit unknown images to your county extension agent to confirm their identity.