This is a region in pre-apartheid South Africa centred in the southern central Transvaal incorporating Johannesburg and Pretoria. It comprises the Magaliesberg, Pilanesberg and the Witwatersrand mountain rainges. It extends south to the Vaal river and north to the Pilanesberg. Of the 750 tree species to be found in the Transvaal, more than 160 are found in this region.
Named in honour of the renowned plant collector Carl (Karl) Ludwig Philipp Zeyher (1799-1858). One of South Africa's foremost botanical collectors who is synonymous with his collecting partner Ecklon. He began collecting in the Cape in 1822, undertook a major expedition to Kaffraria (the Eastern Cape) 1831-1832 and to the Transvaal from 1840-1842.