This photo shows 2 termite nests the top part of which are clinging around tree trunks. The termites from the one on the left have completely consumed the leaves and bark of their tree. It is important to realise that the vast majority of the mass of these termites nests is underground. These visible parts are mainly just providing ventilation for the underground nest. In fact in this photo the 2 visible parts on the trees here may actually be from the same underground nest.