Wild cherry dosage should not be exceeded due to cyanide content.
– Toxic and less toxic plants. 39. Prunus padus, Prunus serotina — Haupt H. — Kinderkrankenschwester. 1998 Nov;17(11):504-5.

Do not use if you are pregnant or nursing.

Hydrocyanic or prussic acid contained in the leaves, especially wilted ones, can be deadly in cattle.
– Forest Grazing Hurts — by Bob Dewitt — Resource Forester — New Franklin

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