Poisonous Plants

Introduction

Poisonous plants are common in Colorado’s pasture and range and generally are avoided by livestock. However, there are situations where livestock poisoning is more likely to occur.

  1. Lack of other forage to eat because of an overgrazed pasture or a dry year.
  2. Animals are new to the area (from another state where they are not trained to avoid certain plants).
  3. Animals are grazing in snow cover and the only plants sticking up from the snow are poisonous.
  4. Dose makes the poison (livestock usually need to eat a lot to be poisoned).

Poisonous plant resources:

Knight, A., Walter, R. (2001). A Guide to Plant Poisoning of Animals in North America. Teton New Media: Jackson, Wyoming.  A comprehensive book of poisonous plants in Colorado.

Guide to Poisonous Plants website – search by plant name or clinical sign.