An autopsy of two moose found dead in a Silverthorne yard determined the animals had been poisoned by ornamental yew.

In an interview with CBSDenverRachel Gonzales, Colorado parks and wildlife officer, said when the moose were found in March, there was no evidence they had been attacked or injured.

“They were thin but that’s not uncommon at this time of year. Most animals have lost their fat stores over the winter and things aren’t green enough for them yet,” Gonzales said in the interview.

A toxicology report revealed that the moose had ingested yew leaves, which are non-native and incredibly poisonous.

“Yews contain a group of highly toxic alkaloids. All green or dried parts of the plant except the fleshy part of the aril surrounding the seed are poisonous. The highest concentration of alkaloids is usually found in the leaves in winter. Adult cattle and horses have been fatally poisoned with as little as 8 to 16 ounces of yew leaves,” Colorado State University said. Guide to poisonous plants said.

According to the guide, ingesting the plant can cause vomission, diarrhoea, mmuscle tremor, difficulty in breathing, convulsions and sudden death.

This tragic accident reminds homeowners to always do research before introducing new plants to their yard.

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