People are being asked to notify the Peak District National Park Authority if they have planted any ash trees in the past six years, and to choose alternative trees in any new planting schemes.
The appeal is part of a national alert over ash dieback disease, caused by the fungus chalara fraxinea, a serious threat to Peak District ash woodlands which are among the most important in the UK and of international significance.
Access to woodlands is unaffected, but the PDNPA is asking people to be vigilant about cleaning footwear, clothing, cycles or buggies so as not to transfer the fungus spores from one site to another.
Seven limestone dales in the national park contain some 900 hectares of ash woodland. They include iconic landscapes such as Lathkill Dale, Dovedale, Monsal Dale and the Manifold and Wye Valleys.
Jane Chapman, head of environment and economy for the PDNPA, said: “This is a serious disease and if it took hold in our woodlands it would change some of our most iconic landscapes irreversibly.
“No cases have been found in the Peak District, but if we are going to get an outbreak, new trees are the most likely source of infection.”
People who have planted ash in the past six years should call the Authority’s Customer Service on 01629 816200 or email email@example.com giving their name, contact details and the site location.
If people suspect any cases, they should check the symptoms through the Forestry Commission’s website, www.forestry.gov.uk/chalara or http://www.youtube.com/watch?v=8sI7hgFZ-4g&feature=youtu.be Then email the Forestry Commission firstname.lastname@example.org or phone 0131 314 6414.