An area of 19.05 hectares (47.1 acres) of the gorge is a biological Site of Special Scientific Interest;[1] it was notified in 1986.
The steep wooded banks constitute one of the few remaining ancient, semi-natural woodland sites in Falkirk District.
[2] Plants found here which are rare in Falkirk District include alternate-leaved golden saxifrage (chrysosplenium alternifolium), moschatel (adoxa moschatellina) and hemp agrimony (eupatorium cannabinum).
The site also contains pendulous sedge (carex pendula) and lily of the valley (convallaria majalis) both of which are uncommon in Scotland.
[1] The Avon Gorge is one of the few remaining oak-dominated woodlands in the central belt of Scotland, others include the nearby Callendar wood.