Walkers are being urged to keep on paths through Guernsey’s Bluebell Woods to protect the threatened flowers.
Bluebells are declining there as the dominant white-flowered Allium triquetrum continues to spread.
The government said bluebells are very sensitive to trampling and that where people stray from the path they are less able to thrive.
They said they will be “improving demarcation of the main pathways” and improving signage.
A spokesperson for Agriculture, Countryside and Land Management Services (ACLMS) said the Allium triquetrum, also known as three-cornered leek or stinking onions, emerges early in the year, getting a head start on native plants such as bluebells.
They said: “Where people walk into the area of bluebells, possibly to take photos, this unfortunately leads to walkways that encourages others to follow.
“This creates bare ground and introduces seed which accelerates the spread of the invasive Allium directly into new areas of bluebell so that in time these dominant groups of bluebells may well be lost.”
They added there was “no guarantee that the bluebells can be saved” but that “doing nothing will inevitably lead to their gradual loss”.
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