Volunteers are being sought to help restore rare chalk grassland on part of the North Downs in Surrey.
Surrey Wildlife Trust is working to improve the habitat at West Hanger near Shere as part of a three-year project.
The trust wants to protect the grassland and rare plants from being taken over by scrub.
Volunteers have been working to trim vegetation and remove unwanted plants from the reserve, which lies off the A25 between Guildford and Dorking.
A herd of sheep have also been loaned from a neighbouring farm to graze on the land.
The trust said the sheep removed nutrients from the ground, preventing scrub from growing.
Leo Jennings, a ranger with the trust, said the work had had a "really positive impact".
The next volunteer events take place on 20 and 22 February.