Country diary: fungi like ripe peach flesh magnifies the veteran oaks

I’m wary of the way that the new government formula of net gain is being bandied to justify all manner of pet projects. It’s intended to ensure developers leave more nature than they subtract, but the value of landscape isn’t easily measured in simple metrics. Oliver Rackham best illustrated the point when he suggested that 10,000 century-old oaks were not equal to one 500-year-old tree.

By this equation, Moccas Park would be worth a good portion of the rest of this county because it is full of veteran trees. It is one of Britain’s oldest, finest wood pastures and the moment you step through the gates you’re aware of the element that invariably determines real value in nature – time.

Lawn Pool, for instance, directly in front, was first fashioned from meltwaters off the last glaciers grinding through the Wye valley. On all sides you start gradually to pick out the trees: grotesque boss-bellied veteran oaks, or sumptuous teepees of emerald foliage about giant chestnuts. Walk up to the last and you appreciate how the bark spirals through the canopy in deep twisting grooves.

All of the wood, whether living or dead, looks stalagmite hard, but strangely the fungi that proliferate on these parts seem soft and even appetising. A huge specimen of oak bracket looked like one of those home-baked flatbreads dusted in spelt flour, while its goo-studded rim suggested a particularly delicious kind of honeyed halva. One gorgeous plump specimen of beefsteak fungus reminded me of ripe peach flesh.

The last was growing on arguably the oldest and most important of all these irreplaceable oaks: the Old Man of Moccas. I have no problem with his exalted status. It is, for example, one of the few trees here that holds a beetle (Hypebaeus flavipes) found nowhere else in Britain. Its gender, however, seems inexplicable.

Its one inescapable feature is the way the bark, top to bottom through its six-metre-high boll, seems to have been peeled back into two thick-rimmed labia. From between these surface ripples is borne a protean mass of tissue that is upswollen with a sense of enduring life. A friend has since suggested an alternative: the Mother of All Moccas.

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