  We study the Fibered Isomorphism Conjecture of Farrell and Jones in L-theory
for groups acting on trees. In several cases we prove the conjecture. This
includes wreath products of abelian groups and free metabelian groups. We also
deduce the conjecture in pseudoisotopy theory for these groups. Finally in B of
Theorem 1.1 we prove the L-theory version of [[7], Theorem 1.2].
