Drones have been used to scatter around 20 million birch tree seeds on the hillside above a notorious stretch of road in Scotland which is often affected by landslips.
The experimental project is part of efforts to shore up the A83 at Rest and Be Thankful in Argyll, which is frequently rendered impassable.
It is hoped that planting native tree species on the slopes will lead to the development of an extensive root system, making the underlying soil more secure.
It is the first time that drones have been used by Forestry and Land Scotland (FLS), which manages the nation’s publicly-owned forests, specifically to spread seeds in this way.
It said the technique allowed millions of birch seeds to be dispersed in “a matter of hours” across an area of around 12 hectares (30 acres), which would have taken weeks if done by hand.
After a temporary “landing pad” was built on the hillside, a drone was loaded with seeds and given a pre-programmed flight plan to sow the seeds from above.
FLS staff are now planning further drone flights around the A83 and believe the technique has “huge potential” for deployment in other difficult and potentially dangerous locations.
James Hand, woodland creation forester at the organisation, said: “This is a major innovation that we expect will soon be adopted across the country as we work to adapt our forests and the wider landscape such that they can better withstand the impact of a changing climate.
“Planting within the landslip area would have been virtually impossible given the risk of dislodging boulders and unsafe conditions for people to work.
“If only 1 per cent of those seeds is successful that will mean 200,000 trees will soon be growing on this slope, their roots slowly binding the soil and making it much more stable.
“In effect, we’ll be capturing carbon emissions in these growing trees and putting it to work to protect road users and the carriageway.”
The A83 runs for almost 100 miles, connecting the Mull of Kintyre and southern Argyll to the shores of Loch Lomond, with around 1.3m vehicles using the route each year.
However, the section known as Rest and Be Thankful is highly vulnerable to landslides and in 2020 alone was closed for a total of 200 days.
When this part of the road is forced to close, an old military route underneath it can be used, but if this is also affected by landslides then travellers face a 59-mile diversion.