WALKERS are being asked to avoid parts of the Chinese Gardens at Rivington as a long-term project to heal a serious plant and tree disease gets underway.

Woodland experts were called in to remove all the rhododendrons affected by the disease.

Although some areas in the Chinese Gardens will be cordoned off while the work takes place, visitors will still be able to walk along many of the paths.

The problem was first spotted earlier this year following tests by the Department for Environment, Food and Rural Affairs at Rivington after which some plants were removed.

But further samples have shown the disease - Ramorum Blight - has spread to many more areas and 21 hectares will be removed within the next two years.

Nick Taylor, of United Utilities, which owns the land, said: "The Chinese Gardens are popular with walkers all year round, attracting hundreds of people every week.

"People will still be able to walk on many paths in the gardens, but we are asking everyone to stay away from the areas which have been cordoned off.

"The disease will not make you ill and does not pose any threat to your health, but if someone walks through a cordoned off area they could spread the disease further afield via the spores on the soles of their shoes."

Woodland experts are tackling the problem by cutting down diseased plants and then burning the stumps to treat the remains.

Mr Taylor said: "We've got six teams working on this problem and we aim to get the Chinese Gardens back to normal as soon as we can.

"We will be replanting alternative plants in areas which have been cleared and people can rest assured the gardens will look their best again after we've carried out this work."

The water supply from the reservoirs at Rivington and Anglezarke will not be affected.

The United Utilities catchment team at Rivington is one of four in the North-west which manages the land as part of the reservoir protection work, providing natural barriers or filters such as heather, between the land and water.

Ramorum Blight was first detected in parts of coastal California where it ate into tan oak trees and was known as Sudden Oak Death.