Acorn

Acorns of Sessile Oak

Acorns of Lithocarpus collettii

Acorns of Quercus macrolepis

The acorn is the fruit of the oak tree. It is a nut, and has a single seed (rarely two seeds), enclosed in a tough, leathery shell. Acorns vary from 1 – 6 cm long and 0.8 – 4 cm broad. Acorns take between about 6 or 24 months (depending on the species) to mature.

Acorns are one of the most important wildlife foods in areas where oaks grow. Creatures that make acorns an important part of their diet include birds, such as jays, pigeons, some ducks and several species of woodpeckers. Small mammals that feed on acorns include mice, squirrels and several other rodents. Such large mammals as pigs, bears, and deer also eat large amounts of acorns: they may constitute up to 25% of the diet of deer in the autumn. In some of the large oak forests in southwest Europe, traditionally called "dehesas", pigs are still turned loose in oak groves in the autumn, to fill and fatten themselves on acorns.

Acorns contain tannins, which are toxic to some animals such as horses. The tannins can be soaked out, using water.

Acorn Media

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  European oak acorn (length 25 mm)

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  Acorns from small to large of the Willow Oak, Q. phellos (very small, at center); the Southern Red Oak, Q. falcata; the White Oak, Q. alba; the Scarlet Oak, Q. coccinea; from southern Greenville County, SC, USA. Scale bar at upper right is 1 centimetre (0.39 in).

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  Diagram of the anatomy of an acorn: A.) Cupule B.) Pericarp (fruit wall) C.) Seed coat (testa) D.) Cotyledons (2) E.) Plumule F.) Radicle G.) Remains of style. Together D., E., and F. make up the embryo.

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  Ponies eating acorns. Acorns can cause painful death in equines, especially if eaten to excess amounts.

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  Sprouting acorn of Quercus robur

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  Mortar holes for pounding acorns into flour, Lost Lake, California

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  Chuckachancy women pause in their work preparing acorns for grinding, California, ca. 1920

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  Campaign hat worn by General Sherman

Other websites

• Nutrition Facts for Acorn Flour
• Nupa Acorn Soup (Miwokan recipe)
• Cooking With Acorns: A Major North American Indian Food
• How to whistle an acorn