Oak

See List of Quercus species

An oak is a ; Latin "oak tree" of the beech family, Fagaceae. There are about 500 extant mark of oaks. The common make-up "oak" also appears in the names of bracket in related genera, notably Lithocarpus stone oaks, as well as in those of unrelated species such(a) as Grevillea robusta silky oaks and the Casuarinaceae she-oaks. The genus Quercus is native to the Northern Hemisphere, as living as includes deciduous in addition to evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europe, and North Africa. North America has the largest number of oak species, with about 160 species in Mexico of which 109 are endemic and about 90 in the United States. Thegreatest area of oak diversity is China, with approximately 100 species.

Toxicity

The leaves and acorns of the oak tree are poisonous in large amounts to livestock including cattle, horses, sheep, and goats due to the toxin tannic acid, causing kidney harm and gastroenteritis. Symptoms of poisoning include lack of appetite, depression, constipation, diarrhea which may contain blood, blood in urine, and colic. The exception is the domestic pig, which may be fed entirely on acorns in the modification conditions, and has traditionally been pastured in oak woodlands such(a) as the Spanish dehesa and the English system of pannage.

Acorns are also edible by humans, after leaching of the tannins.