‘It secretes a sap that burns the skin and causes blisters. It’s a photosensitivity problem, I think. But it can cause temporary blindness, and in some cases serious long-term damage such as recurrent dermatitis. You daren’t cut the things down with a strimmer without wearing protective gear. They’re a real menace.’

‘Vernon Slack had blisters on his hands,’ said Fry.

‘He got them from touching giant hogweed while he was crossing the stream at Litton Foot.’

‘On his way to Fox House Farm.’

‘Yes.’

‘Apparently, he used to leave his motorbike at Tom Jarvis’s, then cross the stream and climb up through the woods. He told Jarvis he was doing a bit of poaching on the Alder Hall estate. He probably left him a rabbit or a pheasant occasionally, as proof.’

‘Did Jarvis ever suspect there was more to it?’

‘We don’t know,’ said Fry. ‘He doesn’t say.’

‘No, he doesn’t give much away. But it’s best to pay attention to what he does say.’

Fry frowned. ‘He was clearly being intimidated by someone. I think the poachers must have been trying to warn him away from their territory, don’t you? All that business with the dog and the bag of excreta.’

‘I never thought Tom Jarvis was the type to be easily intimidated,’ said Cooper.

‘Maybe.’

Cooper reflected that there had never been any evidence that the bag had actually existed, either. Mr Jarvis might have had reasons of his own for laying a false trail.

Fry parked at the edge of the picnic area, near enough to reach the carved miner overlooking the road. Cooper remembered these carvings from when the wood had been a sort of reddish golden brown. Now they were weathered from exposure and had developed a patina of green mould.

‘There must still be some of Audrey Steele’s bones scattered across the hillside over there,’ said Cooper. ‘I don’t suppose we’ll ever find the last bits of her.’

‘We’re not even looking for them any more,’ admitted Fry.

‘So they’ll stay there for ever, unless they turn up in a bird’s nest some day.’

‘What’s the matter, Ben?’

‘I’m wondering whether it’ll make any difference to her family. They thought they already had all of her once. Then Audrey turns up again, but some of her is missing. I’m not sure how I’d feel about that myself. I’m trying to work it through in my mind.’

‘If you really need to know, you could ask them,’ said Fry.

Cooper looked at her, feeling a brief pity at her lack of experience in human relationships.