Nikola Damjanov’s terrain handbook series covers Houdini terrains in depth.

Houdini has excellent terrain tools to build realistic landscapes by generating and shaping height fields. Check out this series from Nikola Damjanov that covers everything you will need to understand and create terrains in Houdini.

The series starts from a foundation layer of heightfield nodes and covers their functions. Nikola also covers how to generate masks to create textures in COPs, scatter geometry using those masks, and how to apply and render them in a LOPnet with Karma.