There isn't an easy method for erasing subgraphs. However, the subgraph template does declare its list of children (m_children) to be public, so if you have an iterator to the subgraph you want to delete, you can just do sg.m_children.erase(i). Note that children_iterator isn't the same as the iterator type of m_children. I think you can translate to it using children_iterator::base().