Yes, some species of yucca plants can be toxic to cats. Yucca plants contain compounds called saponins, which can be harmful if ingested by cats. The severity of the toxicity can vary depending on the species of yucca and the amount ingested. Ingesting yucca plants can lead to symptoms such as vomiting, diarrhea, drooling, abdominal pain, and in severe cases, even more serious health issues.