Miles Irving is down on his haunches in an English field. All around him are vegetables and herbs - tomatoes, parsley, coriander, lettuce and more - but that's not what he's looking for. He's picking Fat Hen, a spinach-like plant considered a weed by many, including the farmer who owns this corner of Kent, but not by Irving. ''These plants are regarded as vagabonds,'' he says. ''What we're doing is bringing these vagabonds off the street; these weeds are now being used in some of the most celebrated meals in the world.''
That's happening particularly in London, where Irving supplies a number of the best restaurants - including those run by Jamie Oliver, Richard Corrigan and Mark Hix - with foraged ingredients, including salad leaves, wild fruit, seeds, mushrooms and crayfish. Irving, 45, set up his business, named Forager, 10 years ago and, in the time since, a field-change in attitudes to wild food has taken place among Britain's best chefs.
A similar movement is taking hold in Australia, and Irving will be in the country later this month to appear at the Margaret River Gourmet Escape. He'll share his knowledge of foraging and help to address the question of whether insects could ever feed the world. He'll also be spending some time in Adelaide, where his son, Ezra, 25, is moving to work for Jock Zonfrillo, a friend of Irving's and a fellow wild food devotee.
Like Zonfrillo, Irving believes the potential for foraging in Australia is enormous and thus far largely unexplored.
''I want to get involved in trying to kick-start a greater interest among the restaurants in Australia,'' he says.
''You can reel off the wild foods that are eaten in Australia: bush tomatoes, Wattleseed, Davidson's plums, quandong, lilly pillies. They're great ingredients but when you consider the extent of Australian flora - I think it's something like 10 times what there is in Europe - there's got to be lots of buried treasure.'' If the depth and variety of what Irving sources in England is anything to go by, Australia can brace itself for a boom in wild food on restaurant menus. A trip round the storerooms at his base in Chartham, Kent, is informative: there are boxes labelled with the names of any number of well-known London restaurants, and samples of dozens of different types of wild food: seaweed tips, for example, or candied rose petals.
''We use what's growing wild in the landscape to make a point about how productive the natural world is, how strong those ingredients are,'' he says.
Any cook worth his or her salt would be interested in this stuff - as Irving proved when he first encountered Jamie Oliver and convinced him to put wild food on the menu at his restaurant Fifteen.
Actually, he admits, it was more of an ambush than a meeting. ''He came to the Goods Shed [a farmer's market in Canterbury, near where Irving lives] to meet local producers,'' he says. ''I wasn't actually invited but my mate was running the vegetable stall at the time, so he decided half of the stall was going to be given over to mushrooms, and we went out and picked every one we could find. We laid a trap and waited … eventually he got round to us, and [Irving mimics Oliver's mouth falling open] … 'You like that then?' I asked him. 'It's amazing!'''
But while leaves, seaweed and mushrooms are an increasingly easy sell, there are still a few cultural problems to be hurdled - insects, for example. ''I'm all for eating insects,'' he says. ''It's normal: the majority of people on this earth eat insects. We're the funny ones.
''When insects descend on crops, it's often described as a bad thing - but there are places in Africa where people plant crops as bait. The reason they're growing maize is to attract locusts, to harvest them. They've converted a bland starch - maize - into a super food, locusts.''
Irving is clearly excited by the potential of wild food, and nowhere more so than in Australia. He believes it could redefine Australian cuisine, and even Australia itself. ''There's the potential to create a true Australian cuisine, not a sort of cuisine based on European and Japanese cooking shuffled up like a pack of cards,'' he says.
''You'd be using the flavours from that landscape, the wild meats, the plants which are yet to be properly looked at. That's something every Aussie could be proud of.
''Bush food could be key for some kind of movement to bring white Australia and the native community together … That's a great opportunity.''