We study a hierarchical model of non-overlapping cubes of sidelengths $$2^j$$
2
j
, $$j\in {\mathbb {Z}}$$
j
∈
Z
. The model allows for cubes of arbitrarily small size and the activities need not be translationally invariant. It can also be recast as a spin system on a tree with a long-range hard-core interaction. We prove necessary and sufficient conditions for the existence and uniqueness of Gibbs measures, discuss fragmentation and condensation, and prove bounds on the decay of two-point correlation functions.