The Apsley Macleay Gorges are a meeting point for moister eastern coastal and dry western floras, and some 950 native plant species have been identified, of which 36 are rare or threatened.
The dry rainforest that occurs throughout the park is of special interest. Dry rainforest is visible as dense, dark green patches throughout the gorges, favouring hollows where there is shelter from wind and sun, access to more ground water and where the slope is more stable. This vegetation is generally restricted to gullies and broad concave slopes facing south and east.
Dry rainforest communities in the gorges contain at least 187 plant species. These communities are diverse and range from tall, moist forests with rock orchids and felt ferns to shorter, drier communities with a mallee type habit where conditions are harsher.
Dry rainforest can survive in low rainfall areas and is characterised by species such as:
- Moreton Bay fig
- native olive
- shiny-leaved and giant stinging trees
- gorge mock-olive
- scentless rosewood
- red kamala.
The gorge wattle is a rare species that mainly grows in the Apsley Macleay gorges.
Woodland occurs on most slopes, particularly on northerly and westerly aspects. The eucalypt dominating this woodland is forest red gum, identified by the bark on its trunk which sheds to expose white, grey or bluish patches. Silvertop stringybark and yellow box are also present.
Black cypress pine is sometimes associated with these eucalypts, and particularly favours areas of lower rainfall and steep, well drained soils such as the Dangars-Mihi and Apsley-Tia areas.
Various kinds of daisy bush occur in this gorge woodland as well as cassinia and Australian indigo.
Dry eucalypt forests
There's grassy tableland open forest around the rim of the gorge and on sheltered slopes, dominated by various eucalypts. The main species are:
- New England stringybark
- silvertop stringybark
- yellow box
- Hillgrove box
- apple box
- New England blackbutt
- Hillgrove spotted gum.
Native broom and wild cherry are also common. The understorey is often sparse except for occasional wattles, blackthorn and grass trees.
Areas of hardy shrubland occur on the cliffs where the soil is too shallow and unstable for trees. Rapid drainage and strong winds also contribute to the shrubs' twisted and stunted appearance.
The cassinia, geebung, woolly pomaderris and mintbush are the most common species in the area. Because of the harsh conditions some species have adaptated to reduce water loss, (e.g. small leaves and stunted shapes). Wollomombi wattle and the rare Acacia ingramii are quite often found in this shrubland environment.
Because the conditions are extreme on the cliffs, quite a number of rare and uncommon shrubs are found there. These include:
- broadleaf hopbush
- Dodonaea rhombifolia
- Dodonaea serratifolia
- Bertya sp.
- Hakea fraseri
- Westringia sp.
- Grevillea obtustiflora.