The generic name morus, proposed by Linnaeus, was taken directly from the Latin morum, from the Greek morón, and alludes to the black mulberry bush. The wood is very hard and resistant to changes in humidity, so that it is used in the construction of tool handles. It is a fast growing tree that can live up to 100 years. We find two species of mulberry in the alcázar, this one called white and the black mulberry, both from Asian temperate and subtropical areas. They are very sturdy trees grown in the Mediterranean region from at least the period of al-Andalus, being the main food of the silkworm. The production and trade of silk were key elements in the al-Andalus economy. The ancient Silk Road, which began in China and crossed Eurasia, was revitalized by Arab merchants and medieval Jews after its decline linked to the fall of the Roman Empire, being al-Andalus the westernmost point of this ancient route generated not only a network of exchange of goods but also of ideas and knowledge. Silk factories helped the late medieval Islamic Kingdom of Spain, the Nasrid of Granada, to generate enough revenue that allowed them not only to pay the taxes that the Christian kingdoms demanded them in exchange for not invading their territory, but even prompted a net of wealth with the support of Catalan and Genoese merchants and self-expansion of the crops related to silk in the Mediterranean.