Will horses eat the poisonous plants that will poison them?

No, horses generally avoid eating poisonous plants. Horses have a sophisticated sense of smell and taste that allows them to detect and avoid toxic substances. This aversion to poisonous plants is an evolutionary trait that has helped horses survive in the wild. While some horses may occasionally ingest small amounts of poisonous plants out of curiosity or due to lack of alternative food sources, they typically avoid consuming large enough quantities to cause serious harm.