An ambitious drone tree seeding trial in the southwest – one of the largest ever using native tree seeds – could “revolutionise” the expansion of rainforests.

In a project led by the Woodland Trust, high-tech drones, weighing 110kg and able to carry 58kg of seeds, have scattered 75,000 seeds across the rolling hills around Bodmin.

The drones, which hover just a few metres above the ground, can reach areas inaccessible for human planting by hand. Working with the South West Rainforest Alliance, the Woodland Trust hopes the new seeding technique will help triple the area of Temperate Rainforest in Devon and Cornwall by 2050, from 8% to 24% of land area.

Sam Manning, Project Officer for south-west rainforests at the Woodland Trust said: “Rainforest once covered 75% of Devon and Cornwall but we have lost 90% of it. These are among the most threatened ecosystems on earth. They are biodiversity hotspots, home to over 2000 species of lichen. Sadly, rainforests cover just 1% of the Earth’s land surface, and we are one of only a small handful of rainforest nations left on Earth.

“Restoring and expanding our temperate rainforests are vital to solving the climate and biodiversity crises. A key part of that is developing innovative methods of woodland creation which are faster, cheaper and reach inaccessible sites, unsafe for human tree planters, or places where soils are too thin for planting with spades.

“Drones are potentially much faster and cheaper at dispersing seeds than volunteers. The other aspect is safety and accessibility. Many potential woodland creation sites are either too steep, unsafe or remote for people to plant or scatter seeds. Drones can help solve these issues by removing the safety and accessibility limitations of humans.”

The drones, which seeded 11 hectares of land in eight hours, scattered tree seeds that are native to rainforests, including pedunculate oak, alder, wild cherry, downy birch and hazel.

The seeding has included developing “control areas” across sites to test the difference between drone seeding and the natural regeneration of rainforests. The Woodland Trust aims to return to all the trial sites following drone seeding at intervals over the next three years and assess the success rate of germination rate of the seeds, and later, how the planted trees are developing.

Sam Manning added: “We hope to see a success rate of seed to the tree of at least 25% for this trial, which in turn could inspire practitioners and funders to invest time and money into refining the effectiveness of drones for woodland creation.

“Currently only a few companies with legal permissions exist, however this is rapidly changing. Another major bottleneck is around the supply chain of tree seeds for drone seeding projects of this scale. We hope increasing demand for this kind of product will lead to an increasing supply chain and could revolutionise woodland creation.”

The trial is funded by the Woodland Trust’s ‘Rainforest Recovery’ Project through DEFRAs Species Survival Fund.

Rainforest Recovery is the South West strand of The Rainforest Restoration Project. It is being led by the Woodland Trust in partnership with Plantlife. This project is funded as part of the Government's Species Survival Fund. The fund was developed by DEFRA and its Arm's-Length Bodies. It is being delivered on behalf of DEFRA by The National Lottery Heritage Fund.