A helicopter was drafted in to spray bracken on Ilkley Moor in the latest effort to keep the overgrown plants at bay.

More than 75 acres of land on the lower slopes of the moor, the most popular area for visitors and dog walkers, was sprayed with herbicide Asulam.

Supporters group The Friends of Ilkley Moor recently set aside £10,000 to pay for the treatment, which it is hoped will prevent bracken taking over large areas of the landscape.

Friends chairman, John Stidworthy, said: “We are hoping that the chemical will destroy a large area of bracken and that the money will be well spent by the Friends.

"We will not know for sure until next year when the bracken comes up – or, we hope does not.”

Areas of the moor sprayed included land north of White Wells Cottage, land to the west of Spicey Gill, and land close to the Cow and Calf Rocks.

The chemical is said to be harmless to humans and to plant life on the Moor other than bracken and ferns.

More work is expected in the years to come to keep the bracken down. The FOIM are working with landowner Bradford Council on the project.

Richard Perham, of Bradford Council Countryside Services, said: “The spraying of the 75 acres took about an hour and a half, we think we caught the bracken at the right time and hope it will be effective.

"We will need to do follow up treatment in the next few years, chemical and manual.”