Gall oak

Gall oak
Quercus lusitanica
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Fagales
Family:	Fagaceae
Genus:	Quercus
Section:	Lepidobalanus
Species:	Q. lusitanica
Binomial name
Quercus lusitanica Lam. 1785
Synonyms
List Quercus fruticosa Brot. Quercus humilis Lam. 1783, illegitimate homonym not A. DC. 1805 nor Walter 1788 nor Mill. 1768 Quercus valentina Cav. Quercus ovalifolia Bosc ex Pers. Quercus glauca Bosc ex Loisel. 1825 not Thunb. 1784 Quercus australis Link Quercus undulata K.Koch 1846 not Torr. 1827 nor Kit. 1864 nor Engelm. 1878 nor Benth. 1841 Quercus prasina Bosc ex Endl. Quercus aegilopifolia Boiss. ex Endl. Quercus muricata Palau ex Willk. & Lange Quercus quexigo Cook ex Willk. & Lange Quercus aegylopifolia Boiss. ex A.DC. Quercus brachycarpa Kotschy ex A.DC. 1864 Quercus brachycarpa Guss. ex Parl. 1867 Quercus rigida K.Koch ex A.DC. Quercus baetica H.Buek Quercus zang Dippel

Quercus lusitanica, commonly known as gall oak, Lusitanian oak, or dyer's oak, is a species of oak native to Morocco, Portugal, and Spain (Galicia, western Andalucia).Quercus lusitanica is the source of commercial nutgalls. These galls are produced by the infection from the insect Cynips gallae tinctoriae. They are used for dyeing.

Several other species are known colloquially as "gall oaks;" indeed, galls can be found on a large percentage of oak species. The specific epithet "lusitanica" refers to the ancient Roman Province of Lusitania, corresponding roughly to present-day Portugal and Extremadura in Spain.

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