Trees in ancient Sidmouth woodland have been damaged in the construction of alleged illegal mountain bike trails.
Oak, beech and sweet chestnut trees planted more than 200 years ago in Harpford Woods and used during the Napoleonic Wars to provide timber for ships were found with bark stripped or nails hammered into them.
Employyees of Clinton Devon Estates (CDE) was left shocked to find a series of deep pits and ramps dug through the woods and believes the culprits were using the site for illegal mountain bike trails.
The landowner said the damage was caused at the end of last week when unauthorised bike trails were created.
Itis appealing for information.
A CDE spokesman said: "Nails hammered into trees could easily injure unwary passers-by, dumped waste could harm wildlife, and cutting away bark can severely damage or even kill trees."
The spokesman said CDE would be seeking to recover the costs of making the area safe and repairing the damage.
CDE manages around 1,800 hectares of woodland in the county.
John Wilding, head of forestry and environment of the estate, said: "Such ancient woodlands are steeped in history and their beauty is enjoyed by thousands of responsible visitors every year. But a thoughtless minority responsible for this criminal damage is spoiling it for everybody else.
"It is bad enough that trees have been deliberately damaged by people hammering in nails and ripping off bark, but even more worrying is that machinery we use to harvest mature timber could very easily be tipped over by hidden pits or ramps, with potentially fatal consequences for forestry workers.
"We're more than happy to share the enjoyment of Harpford Woods with people who come to walk along the permissive pathways, and to cycle and ride horses along the bridleway which follows the route of the old railway line.
"We know that it is only a very small minority who don't care about the damage they are causing, but the damage is severe."
Anyone with information is asked to email 101@dc.police.uk or call 101.
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