The land added protects areas of old growth forest. There is a network of roads giving 2WD vehicle access. One result of the addition from Clouds Creek SF is the inclusion in the NP of several kilometres more of Nymboida River. This is of considerable interest to recreational users and canoeists. There is an addition on the northeast, bounded by the Tops Forest Road.
Habitats protected include cool temperate rainforest and sub-alpine swamps.
The other section is from Bulahdelah SF, east of Boolambayte. This extends from O'Sullivans Gap FR, southward to the end of the forest, about 2.5 km north of Violet Hill. Includes rainforest and old growth forest. Roaded by Horseshoe Road. 69,529 ha Toonumbar NP - 15559 ha added Separate additions have been made to the east, west and south, with land from four or five different SFs.