Roleybushcare has won the Landcare Group category of the National Landcare Awards

The conservation group invented hydraulic tree injectors, enabling trees to be treated with an environmentally friendly fungicide.

Each month, Roleybushcare volunteers inject vulnerable trees, including jarrahs, banksias and she-oaks, with the fungicide to prevent dieback from spreading and killing plants in Roleystone bushland reserves.

The treatment provides five years of protection from the disease.

On September 18, Roleybushcare was named the winner of the Landcare Group category at the National Landcare Awards.

The award recognises an outstanding community group that works towards sustainable land use and undertakes on-ground action to protect, enhance or restore an area on behalf of the community.

Volunteer co-ordinator Diane Horgan, who has been involved in Roleybushcare for 20 years, said it was an honour to receive the national award.

‘We were surprised to get the 2013 State Landcare Award, so it’s pretty incredible for a group of volunteers in the Roleystone Hills to get a national award,’ she said.

Ms Horgan said volunteers had treated more than 18,000 trees and worked with the City of Armadale to ensure 20 bushland reserves in Roleystone had a registered custodian.

She said chairman Dr Ian Colquhoun, a scientist living in Roleystone, founded the group in 1994 as he could see that dieback was already present in the area.