What plants poisonous to horses can be found in Montana US?

In Montana, several plants are known to be poisonous to horses, including yellow star thistle, hemlock, and various species of nightshade. Yellow star thistle can cause a condition known as "chewing disease," while hemlock is highly toxic and can lead to respiratory failure. Additionally, common plants like foxglove and larkspur are also harmful if ingested. It's essential for horse owners to be aware of these plants to ensure the safety of their animals.