Acorns contain tannins that may cause vomiting or diarrhea; larger exposures may contribute to kidney or liver injury. Whole acorns and shells are choking and obstruction hazards. Exposure often happens during outdoor walks, fall yard cleanup, and when pets encounter seasonal decor. Treat any ingestion as a concern.
Acorns are brown, cap-topped nuts from oak trees. Size and shape vary by species; caps detach when mature and leave smooth shells and a woody cup. Fresh acorns are firm and glossy; older ones may be cracked or moldy.
Oak trees drop acorns in late summer and fall. They accumulate under trees, in leaf litter and mulch, and turn up in yards, parks, and wooded areas. People collect them for seasonal decor like wreaths and table displays.
Acorn flour is a niche ingredient used by foragers and in some traditional or regional cooking. It turns up at specialty groceries and farmers' markets and is made into breads, pancakes, or porridges.
