A conjecture of Liggett concerning the regime of weak
survival for the contact process on a homogeneous tree is proved. The
conjecture is shown to imply that the Hausdorff dimension of the limit
set of such a contact process is no larger than half the Hausdorff
dimension of the space of ends of the tree. The conjecture is also shown to
imply that at the boundary between weak survival and strong survival, the
contact process survives only weakly, a theorem previously proved by Zhang.
Finally, a stronger form of a theorem of Hawkes and Lyons concerning the
Hausdorff dimension of a Galton–Watson tree is proved.