What is "quercus lusitanica"

Gall \Gall\ (g[add]l), n. [F. galle, noix de galle, fr. L. galla.] (Zo["o]l.) An excrescence of any form produced on any part of a plant by insects or their larvae. They are most commonly caused by small Hymenoptera and Diptera which puncture the bark and lay their eggs in the wounds. The larvae live within the galls. Some galls are due to aphids, mites, etc. See Gallnut.

Note: The galls, or gallnuts, of commerce are produced by insects of the genus Cynips, chiefly on an oak ( Quercus infectoria syn. Quercus Lusitanica) of Western Asia and Southern Europe. They contain much tannin, and are used in the manufacture of that article and for making ink and a black dye, as well as in medicine.

Gall insect (Zo["o]l.), any insect that produces galls.

Gall midge (Zo["o]l.), any small dipterous insect that produces galls.

Gall oak, the oak ( Quercus infectoria) which yields the galls of commerce.

Gall of glass, the neutral salt skimmed off from the surface of melted crown glass;- called also glass gall and sandiver.
--Ure.

Gall wasp. (Zo["o]l.) See Gallfly.

Quercus lusitanica, commonly known as gall oak, Lusitanian oak, or dyer's oak, is a species of oak native to Morocco, Portugal, and Galicia. 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.