A carriage horse named Deniz died in Central Park on June 9 after collapsing near Strawberry Fields, with a subsequent investigation indicating the horse was likely poisoned by a toxic plant. A necropsy revealed that Deniz had ingested a significant amount of Japanese yew, a plant known to be highly toxic to horses.

According to the findings shared on Tuesday by the Transport Workers Union (TWU) Local 100, which represents the carriage drivers, the horse’s mouth and stomach contained abundant fragments of Japanese yew needles and other plant material. A pathologist at Cornell University’s College of Veterinary Medicine reportedly identified the quantity of yew present in Deniz’s stomach as sufficient to cause death.

Eyewitnesses described the horse’s collapse as distressing, noting that Deniz began thrashing on the ground before succumbing to the poisoning. The incident has prompted a dispute between the TWU and the Central Park Conservancy over responsibility and safety precautions.

Alexander Kemp, the TWU Local 100 Administrative Vice President, criticized the Conservancy for failing to alert carriage operators and park visitors about the presence of deadly yew plants within Central Park. He emphasized that the Conservancy had not issued warnings regarding the plant’s toxicity, which he implied contributed to the incident.

In response, the Central Park Conservancy pointed to park regulations that prohibit horses from consuming any vegetation across its 843-acre grounds. The Conservancy accused the TWU of negligence, asserting that the union and its members should have ensured that horses avoided eating plant material while working in the park.

The Japanese yew, which is not native to the United States, is known within veterinary circles as a highly toxic species for horses, containing compounds that can cause rapid cardiac failure. While the exact circumstances leading to Deniz’s ingestion of the plant remain unclear, the incident has renewed calls for improved safety measures and monitoring to prevent similar occurrences in the future.