Quercus afares × Q. suber. Tree assumed to reach more than 20 m in the wild. Bark somewhat corky, young shoots tomentose. Leaves late deciduous, persisting over winter, ovate to elliptic, tapered to rounded at the base and tomentose beneath, very variable in shape and size, some close to those of Q. suber, others resembling those of Q. afares but smaller, sharply toothed to nearly entire. Petiole very short to 2 cm long. Cups to 2 cm across with recurved scales, acorns ovoid, about 3 cm long, half enclosed in the cup and ripening the second year. (Trabut 1890)
Habitat Mountain forests with the parents at 800–1000 m
USDA Hardiness Zone 6
RHS Hardiness Rating H6
Trabut (1890) stated that this hybrids occur where the lower altitude Q. suber meets the higher altitude Q. afares. He described two forms, Q. × kabylica for plants resembling Q. suber and sometimes difficult to distinguish. These have small leaves, about 5 × 2 cm with 6–7 veins on each side and the margin mostly unlobed but with spiny teeth. The name Q. × numidica was applied to plants resembling Q. afares but with corky bark. These have leaves up to 10 × 5 cm with up to 10 veins on each side, the margin shallowly lobed, the lobes tipped with short teeth. He also mentioned that these trees usually have few or no acorns (Coombes & Vázquez 2021).
Two plants are grown at the Arboretum de Pouyouleix, France grown from seed collected near Yakouren, Algeria in 2014. The largest was 2 m × 3.5 cm in 2020 (B. Chassé, pers. comm. 2020).
The epithet derives from the ancient kingdom of Numidia, which comprised Algeria and parts of Tunisia and Libya.