A tiny rare plant has been brought back from the brink with the help of an unusual conservation technique: running over it with a tractor, experts said.
Marsh clubmoss is an ancient but highly threatened species which resembles a tiny spruce tree and is found on damp heathlands.
It has seen declines of 85% in the past 85 years as its heath habitat has vanished, and in lowland areas is now largely confined to a few strongholds in Dorset and Hampshire.
The Dorset Heathlands Heart project is working to restore the county’s heaths which have declined by 85% since 1800, due to development, tree plantations, agriculture and lack of habitat management, with only fragments remaining.
The team behind the project said marsh clubmoss thrives on bare wet ground created by disturbance such as grazing animals or tracks.
So a dramatic decision was made to deliberately drive over thousands of plants in a five-tonne tractor.
Sophie Lake, co-project manager, said: “We knew that many heathland plants benefit from significant disturbance but there was a sharp intake of breath when we took the decision to drive up and down over a beautiful colony of 3,000 plants in a five-tonne tractor brandishing a muck grab for maximum disturbance.
“Thankfully, the calculated risk has paid off handsomely: where there were once 3,000 plants there is now a thriving colony of 12,000 delighting in the heavily disturbed bare ground necklaced with damp pools created by tyre tracks.”
The low-growing plant, which only reaches around 8cm tall (3 inches) can get crowded out by other vegetation, but needs a beneficial fungi which is found with existing clubmoss and other plants to help it germinate and grow.
This makes the tractor method of creating small bare patches surrounded by plants, rather than large “scrapes” of empty ground, effective for boosting the marsh clubmoss.
English lowland heaths were once well used for grazing livestock and collecting gorse for firewood, heather for thatch, bracken for bedding and sand and gravel for building.
This activity created trampled trackways, exposed sandy patches and shallow pools which were a haven for wildflowers and other wildlife, and the team are attempting to recreate and connect up patches of habitat for nature.
Caroline Kelly, co-project manager, said: “The clubmoss experience has emboldened us in our determination to strategically ‘mess up’ the heaths to restore them to something akin to their former glory.
“The more work we undertake the more we understand and appreciate about how restoring some disturbance is fundamental to heath health.”
Marsh clubmoss is one of 19 scarce and declining species which the Dorset Heathland Heart project is working to protect, including lesser butterfly orchid, chamomile, pillwort and pale dog-violets.
Wildlife including woodlark, sand lizard, heath tiger beetle and the incredibly rare Purbeck mason wasp, which is only found in Dorset heathlands in the UK, are also being helped through the scheme.
The Purbeck mason wasp has been spotted nesting on a new bare clay scrape created on RSPB Stoborough and heath tiger beetles have been seen using sandy scrapes made with an excavator on Dorset Wildlife Trust’s Sopley Common.
Evidence of sand lizards have been found on new sandy scrapes at Stoborough, and yellow centaury has been found in a restored and re-rutted trackway at the reserve where it has not been seen for 20 years.
Conservation charity Plantlife is leading Dorset’s Heathland Heart and is partnering with the RSPB, National Trust, Dorset Wildlife Trust, ARC, Forestry Commission, QinetiQ and the Rempstone Estate.
The project is part of the Back from the Brink plan to save England’s most threatened species from extinction.