Let
K be a nonarchimedean local field, let
L be a separable quadratic
extension of
K, and let
h denote a nondegenerate sesquilinear form
on
L3. The Bruhat-Tits building associated with
SU3(
h) is a tree.
This is applied to the study of certain groups acting
simply transitively on vertices of the building associated with
SL(3,
F),

or

.