A deadly tree disease has been discovered in woodland between Bakewell and Matlock.
The Forestry Commission has confirmed the outbreak of ramorum disease, which affects Japanese larch trees.
The disease can kill larch trees within a year of symptoms first being detectable.
Japanese larch needles also produce huge quantities of the spores that spread the disease, so the trees must be felled quickly to limit its spread.
The outbreak has occurred 80 miles from the nearest previously known outbreak in larch. The exact location of the outbreak is not being released in a bid to prevent further spread of the disease.
Ben Jones, of the Forestry Commission, said: “It’s too early to predict the full implications of this find so far from any other known infected larch woodland. There have been infected rhododendron shrubs in the area, so we are double-checking nearby woodlands.
“Stakeholders will be informed and meetings will be held to raise awareness of the disease and the measures that are required for containment.
“Almost all the other sites that we are most suspicious of at the moment are either close to or contiguous with existing infection sites that were identified in 2009 and 2010.”
The disease causes the trees’ shoot tips to wilt and needles to turn black and fall prematurely. Cankers that bleed resin can appear on the branches and upper trunk. It is not harmful to humans or animals.
Previously the pathogen that causes the disease has been recorded on other plants such as rhododendron and bilberry in South Wales, South West England and parts of the Midlands and North West, including Derbyshire.
However on larch trees it has been confined until now mostly to South Wales and South West England, with single isolated sites in central and northern Wales and western Scotland, and a small number in Ireland and Northern Ireland.
The Matlock outbreak on larch was first noticed during aerial surveys of southern and western Britain and central England to spot possible signs of the disease.
Dr John Morgan, head of the Forestry Commission’s Plant Health Service, said: “We urge everyone to remain vigilant for signs of ramorum disease, not just in larch trees, but also in other vulnerable plants, particularly rhododendron and bilberry.”
Anyone who suspects they have seen the symptoms of ramorum disease should report it to the Forestry Commission on 0117 372 1070.