The Collaborative International Dictionary of English v.0.48:

Landdrost \Land"drost`\, n.; pl. -drosten . Sometimes
   incorrectly Landtrost \Landtrost\ [D., fr. land land + drost
   a kind of official; akin to G. truchsess.] (In South Africa)
   (a) A chief magistrate in rural districts. He was replaced in
       1827 by "resident magistrates."
   (b) The president of the Heemraad.
       [Webster 1913 Suppl.]