• 1968 Lineé Medal (silver) from the Royal Academy of Sciences • 1980 Gold medal from the South African Academy of Sciences • 1980 Recognised by the
Bavarian Academy of Sciences for his contribution to Merxmüller's
Prodromus einer Flora von Südwestafrika Giess is commemorated in the names of numerous plant species, a beetle and a termite. This botanist is denoted by the
author abbreviation Giess when
citing a
botanical name. ==Bibliography==