FOR a tree to survive for centuries, it needs a lot of luck. It needs to avoid disease and lightning, fire and flood, and, more than anything, it needs to avoid man.

Man cleared trees to make fields for his crop. Those trees he left on the field boundaries, he felled to use their timber to build his houses or his ships or to prop up his mines.

So the oldest trees are hidden away in inaccessible locations.

The Northern Echo: Doe Park at the front, surrounded by its caravan site in the beautiful Teesdale countryside

Last week, we told how a 300-year-old walnut tree has been discovered growing quietly in Middleton Tyas, making it the oldest known walnut in County Durham and North Yorkshire. We asked its discoverer, Rodger Lowe, of Teesdale Heritage Trees, to point us in the direction of the oldest of all the trees in the area.

“Normally, we’d be thinking about yews but there aren’t any real contenders in the region I’m afraid,” he says. “We have a couple we can date by the house to 1601 and 1606, but they are not impressive trees yet.

“So the next longest lived species is oak.”

The best guide to a tree’s age – unless you cut it down and count its rings – is its girth, which is the circumference of its trunk as measured 1.5m above the ground.

From the Woodland Trust’s ancient tree inventory, it becomes clear that to be a contender as our oldest tree, an oak has to have a girth of more than six metres.

In Auckland Park, at Bishop Auckland, and in the grounds of Holywell Hall, near Croxdale, there are oaks with girths of 615cms, but the biggest are to be found on the craggy banks of the Tees and its tributaries.

In Selaby Basses – the woodland on the rise up from the river to Selaby Hall to the west of Gainford – there’s an oak with a girth of 660cms.

A little further west, in the grounds of Stubb House, there’s one that’s 670cms.

They are, though, just babies.

At Rokeby, near the Greta, there’s an oak with a girth of 700cms. At Cliffe, on the Yorkshire bank of the Tees opposite Piercebridge, there’s another of the same size.

Now we are coming to the big boys…

On the Durham bank of the Tees opposite Wycliffe, in an area the Ordnance Survey map calls Graft’s Farm, there is a whopper with a girth of 768cms.

But the biggest, by far, is in a remote ravine in Baldersdale, near Cotherstone. It’s girth is 800cms.

“It’s in an elevated location which is wild and woolly, and it’s hidden,” says Rodger. “It grew to a size where it was too big for the handsaws of the old days to cut through and now, even with modern chainsaws, it is in such a bad location, you couldn’t get it out, so no one has bothered with its for centuries.

“It isn’t in the best of growing conditions, and yet it is massive.”

It is on the north bank of the Balder in the grounds of the Doe Park caravan site. It may even have been deliberately left as marker for a parish or property boundary.

“So now you are going to ask me to put an age on it which I’m loathe to do,” says Rodger. “Oak are the most studied species but most of the data is confined to Windsor and the royal parks.

“On the matrix I have, which is based in southern England growing in good conditions, an 8m girth oak is dated at 700 years old, so anything that big up here and in poor growing conditions has to be older.

“800?

“Certainly these trees pre-date almost all of the man-made structures in the country. They are national monuments without any legal status and barely any recognition. Go to other countries, Norway, for instance, and big trees are designated as national monuments.”

The Doe Park Oak must have sprouted from its acorn around 1200. If it could talk, it could tell us so many amazing stories about the slaughter by the Scots, the christening of calves and the headless horseman of Baldersdale. Those, though, will have to wait for another day...