How much research is too much? Can you read more than your brain can take? I'm starting to think so. Several months into the research for my social history of British forests and I've lost count of how many books I've read so far (though come to think of it, actually I haven't as I've been adding the useful ones to a bibliography, which currently has… exactly 100 titles: spooky). Luckily I've always loved reading, but it's more a question of how much information I can absorb.

If the brain is a kind of information sponge, then it seems there comes a point where it needs squeezing out again before it can absorb any more – and that's the stage I've got to. So although it feels weird a slightly wrong, I've stopped reading altogether for a while, in the hope that something useful will start coming out of my head before too long. Hasn't yet, admittedly, but give me time. Just don't tell my publisher, will you?

To Epping Forest on the hottest day of the year so far. Despite the heat I'm excited to be doing my first bit of on-the-spot research for the forests book, and Epping doesn't disappoint, even if I don't find any body parts.

I meet my mate John, down from Essex for the day, at Stratford station, then it's the Central Line all the way to Epping. It feels weird to be on the same tube that was deep under Tottenham Court Road only half an hour ago as it chunters its way through the suburbs and out into open country, and Epping itself has the feel of a well-off country town. There's not much sign of the forest, though we do spot Forest Dry Cleaners as we amble down the high street.

Across Bell Common and a busy back road and the forest suddenly enfolds us. In all the years I lived in London I'd never visited it before, maybe because I'd always assumed it'd all be rather tame and suburban, so it's a surprise how rough-edged and wild the actual forest feels.

Mugging up about it afterwards it becomes clear that, far from being a sign of neglect, the lack of signage and manicuring is a deliberate policy by the City of London, which has owned Epping Forest since 1878. Both John and I have brought our large-scale OS maps and we're generally pretty good map-readers, but even so we get repeatedly, if never catastrophically lost, blundering around in the undergrowth and emerging on fast roads, blinking and disorientated like moles.

Reading Iain Sinclair's typically wonderful London Orbital later it was somehow reassuring that Epping did the same thing to him too: 'There are paths marked out for riders, paths for hikers, but I’ve never walked any distance without getting lost; expecting to emerge in Loughton, finding myself returned to Theydon Bois. Don’t ask me how it works. The spirit of the primeval forest is still present and it abhors trippers, map fetishists.'

By the time we arrive at Chingford, six hours later, we're dusty, sweating and suffering from mild heat exhaustion, but we both feel we've had an adventure, and I can't wait to go back. Back home when I take my walking shoes off my ankles are brown with dust and my shins are covered with bramble cuts, but Epping has got under my skin.

The new (August) issue of Country Living magazine includes a feature about my house, which is, of course, very flattering – though it's also slightly disconcerting to be looking at photographs of the room you're reading an article in; the media equivalent of infinite regression, perhaps.

Just back from the Ways With Words festival at Dartington Hall in Devon. They're funny events, these literary festivals, especially when (like me) you're at the bottom of the pecking order – most people, understandably, are here to hear the big names speak, but us smaller fry get to rub shoulders with them too, which makes for some odd encounters.

At dinner I ended up sitting next to Michael Buerk, whose instantly recognisable voice can carry across a room even at low volume. (How do people do that? As someone so quietly spoken I'm often accused of mumbling it's a skill I'd love to learn.)

Even more alarmingly I was sitting having a quiet breakfast the following morning when who should take the empty place next to me but Roy Hattersley. What does one say to Roy Hattersley? Well, given that I've never had the faintest interest in sport, politics or small dogs the opening gambits seemed limited, and things didn't improve when I asked whether he was driving home.

'No, we're being driven,' he replied, which is something I've always wanted to be able to say to people ever since I overheard a man on a bus having what was evidently a business conversation on their mobile.

Instead of responding with the usual inane 'I'm on the bus', what he said was 'I'm being driven,' which made it sound as if he was reclining in the back of a chauffeur-driven Bentley, not bumping along on the 243 from Dalston Junction.

Very smart, I thought, though I did wonder whether his interlocutor could hear the bus doors beeping in the background.