An abnormal growth on cashew trees, Pistacia vera, Pistacia terebinthus or Pistacia atlantica, that are native to Europe and India. Galls are formed when gall-wasp eggs are deposited on tree branches. The nutlike gall grows until the larvae are completely enveloped. The mature insect bores a hole through the gall in order to escape. The galls contain about 14% tannins (gallic and ellagic acids) along with flavonoid colorants (myricetin, quercetin and kaempferol). The tannins have been used for centuries for vegetable tanning of leather.
Synonyms and Related Terms
Pistacia vera; Pistacia terebinthus; Pistacia atlantica