By Mark Kinver
Science and nature reporter, BBC News
In the early hours of Friday, 16 October 1987, landscapes across the south-eastern corner of England were lost forever.
In a few hours, gusts of wind exceeding 100mph (160 km/h /70 knots) battered woodlands from the south coast to East Anglia.
By first light, an estimated 15 millions trees had been flattened by the worst storm since 1703.
The beech woodland on Toys Hill, the highest point in Kent, had been devastated, losing 98% of its trees. Thousands of veteran trees, some at least 400 years old, were lying prone on the ground.
"We are about 770ft above sea-level here, so we did take the brunt of the storm," said Trevor White, head warden for the National Trust.
It was a story repeated throughout the affected areas. As far are the trees were concerned, the storm could not have arrived at a worse time.
Natural England's woodland and forestry officer Keith Kirby said wet soil from recent heavy rain meant that root systems were not able to offer more resistance to the winds.
"Also, the leaves were still on the trees so that meant there was more weight in the crown and gave them a bigger sail area," he added.
Less than three years later, the equally savage "Burns' Night Storm" swept across the whole of the UK, not just the south-eastern corner of England.
Yet only an estimated four million trees were felled. One reason offered as an explanation was that the 1990 storm arrived in January, when the trees had shed their canopies.
Dr Kirby suggested that changes to the way woodlands were managed were probably another reason why the 1987 storm claimed so many trees.
"A lot of the ancient woodlands would have been managed as coppice during the 19th Century, so they would have been regularly cut over.
Birch has replaced the beech trees that blew over in 1987
He said the system was gradually abandoned because it was no longer providing the products that were needed, particularly after the Second World War.
"A lot of broadleaf woodland had very little management and had grown up; often it was fairly dense.
"They were quite vulnerable because they were tall and had a solid stem that carried a lot of weight. We had a lot of woods that were at that stage."
Trevor White said this was true of Toys Hill, which is owned by the National Trust.
"Until the 1850s, Toys Hill would have been open heathland, where you would have had the right to pannage, which is pigs grazing on beech and acorns," he explained.
"It would have been very open with big mature pollarded beech trees. Cutting off the branches above the grazing line provided grazing material for the animals and firewood for people.
"Then the Act of Parliament to enclose the land (mid-1850s) removed the animals, which then allowed the trees to come through.
"So the trees that blew down in 1987 were the first generation of trees from that time."
Because the hill was effectively a monoculture of mature beech trees of a similar age, it did not surprise Mr White that so many were lost in the storm.
"It would have taken a brave land manager to say, 'right boys, we're going to cut down that hillside in one night', but that is what nature did for us.
"In hindsight, here we are 20 years later and the benefits are quite evident: there is far more varied birdlife than there ever was before."
Nature knows best
As part of the recovery programme on the hill, the National Trust formed a partnership with English Nature to see what would happen if 50 acres (20Ha) of the 450-acre (180Ha) site was left to recover naturally.
"There is a very high percentage of dead wood in there," Mr White revealed, "which is now home to invertebrates, which birds obviously feed on.
"And the fungi are absolutely magnificent, especially at this time of year. There is a very varied ecology; a mature and advanced ecology."
As for tree cover, the area is dominated with self-seeded birch trees. After just two decades, the trees are about 20-30ft (6-9m) tall and are providing enough cover for shade-liking beech saplings to become established.
The areas that had felled trees cleared by heavy equipment have faired less well.
Rotting wood has helped diversify the woodland's ecology
Many of the planted trees are much smaller than those that were self-seeded because the soil had been compacted.
This has made it more difficult for the trees to absorb nutrients and water.
Ray Hawes, the National Trust's head of forestry, said the results have had an impact on woodland management programmes.
"Some of the thinking that has occurred since the Great Storm includes whether we should allow nature more freedom to restock sites and allow natural regeneration," he said.
"With planting, because of the cost, you tend to plant one every two or three metres, so you end up with only 1,000 to 2,000 (trees) per hectare.
"If you allow natural regeneration, then you literally get hundreds of seedlings per square metre.
"So it seems to me that there is a lot of merit in actually allowing nature to do a lot of the selection for us."
He added that he had given quite a lot of thought to how the Trust could make its existing tree stock more resilient to future storms.
"There are a few things that you can do," Mr Hawes suggested. "In a garden, there is a tendency to remove the lower branches to allow views and grow plants.
"But what you are doing is concentrating all the growth towards the top of the tree. So when you get high winds, you are concentrating all the pressure on the roots.
"But if you look at trees with low branches, say in parkland, they all move slightly differently and this acts as a dampener, so the trees are more stable, especially if you give them more room to grow and allow the roots to spread."
As for Toys Hill, Trevor White is hopeful that the scenes of devastation that were revealed on the morning of 16 October 1987 will not be seen again.
"If you take the reasons why the wood blew down, it is because the hill took on exactly the same features because of an Act of Parliament in the 1850s.
"Now we have age diversity across the hill. If we manage the hill to maintain that age and species diversity then that will be a good insurance against it ever happening again."