Here, at 56, Sedaris has found a new hobby: picking up rubbish.

They bought a 400-year-old, two-storey stone cottage on 0.8 hectares in 2010 and took a year to repair its rotted floorboards and mildewed walls. A pig in the backyard that had passed away probably ''died of shame'', Hamrick guessed.

But the real distress has been seeing how people driving through West Sussex litter their environment. ''Since cleaning roadsides has become my life my fingertips have turned black, like spent matches, this the result of prying up bottle caps,'' Sedaris writes in his seventh collection of essays, Let's Explore Diabetes with Owls.

His essay Rubbish was rejected by his usually supportive alma mater, The New Yorker - simply, ''they weren't interested'', he says on the phone from the cottage - but found a home in the Sunday Times Magazine. Sedaris acknowledges ''bitching'' about the problem could turn people off. Still, house guests beware: Sedaris inveigles his international visitors to roll up their sleeves and pick up litter with him. ''They're so good about it. We had people before and after Christmas and when they want to take a walk I say, 'Oh, take a bag.'''

In his essay, West Sussex hardly sounds like all those folksy BBC British rural dramas. ''You know, when I watch shows like that I think, 'Oh, who did the advance work, picking up on the side of the road?' And, 'How much did they get?'''

Nothing, however, could prepare Sedaris for Beijing, recounted in another essay: ''I saw wads of phlegm glistening like freshly shucked oysters on staircases and escalators.'' Chinese babies, meanwhile, ''do without diapers, wearing instead these strange little pants with a slit in the rear. When a child has to go, its parents direct it towards the kerb or, if they're indoors, to a spot they think of as 'kerby'.''

The China visit was made a greater chore by having just visited Tokyo, where ''everything was so delicate and carefully presented'' and the floors and walls of the free public men's rooms in every subway station ''aggressively clean'' - a boon for Sedaris who, since turning 50, ''found that I had to pee all the time''.

Does Sedaris' editor ever say to him. ''Too much, David''?

''No. I mean, surprisingly. You mean like, 'Too much, that's disgusting'? I don't think you can have too much disgusting. Have you been to China? That's what you're going to see when you go,'' he says with a laugh.

Sedaris makes the point in the China piece that he likes eating horse. Presumably the ongoing equine meat scare in Britain and Europe, in which products labelled as beef were found to contain up to 100 per cent horse meat, did not perturb him?

''My feeling is if you're going to buy frozen lasagne at the grocery store and it has some horse meat in it, that's probably the healthiest part of the whole thing,'' he says. ''I rode a horse [just] one time. So I never had that sentimental attachment … Let's say you have to shoot a horse. Why not eat it?''

Sedaris grew up in North Carolina and became famous for writing about his part-time job as a Christmas elf at Macy's.

The new collection covers his international travels, including to Australia, where his readings have filled the Sydney Opera House Concert Hall, and he plans to be back here in January.

The opening essay, Laugh, Kookaburra, one of his personal favourites, was inspired by an encounter with the bird in Daylesford, Victoria. In it he recounts sitting up late during childhood with his sister Amy, repeatedly singing the Australian ditty in defiance of their father. He writes in the essay: ''Cut off your family, and how would you know who you are?''

Despite the distance, does he ever suffer repercussions from writing about his family? Sedaris says he clears tricky stuff with his family before it is published, and rewrote the title essay of the new book because his sister Lisa feared readers would see her in a certain light. ''Usually I'm pretty good at that stuff. Everybody has their secrets and everybody has things they don't want the world knowing. Generally it's all stuff they [also] think is funny.''

One essay that stands out for me, I tell him, is Memory Laps, in which he recounts that his cruelty as a child was a mask for seeking the approval of his father, Lou Sedaris, who withheld it, instead praising another boy's swimming prowess.

Does Lou, who turns 90 in April, still compare his son with others? ''No. It's not as though he says, 'How's that new Jonathan Lethem book!' [At 90] he's not really equipped to do that to me now. He's never been a big reader.

''But I wouldn't want anybody to come away from anything I've ever written feeling like I wish that I had different parents. I'm so grateful to have the parents that I had. I wouldn't change anything about it, because that's my dad. Proving him wrong is what got me out of bed every day.''

Sedaris is a dab hand with a well-turned word image - he describes a flying squirrel as an ''empty hand puppet'' - but his idea of refinement is throwing things away. ''If you write a phrase and think, 'Wow, that's really poetic, that's really pretty, I really nailed it,' you get rid of it [because] you've overdone it.''

Another outstanding piece is Loggerheads, ostensibly about collecting turtles but dealing on a deeper level with Sedaris losing his naivety and awakening to his sexuality which, as an adolescent, he couldn't quite name.

Sedaris' sexuality has long been clear through his relationship with Hamrick, but he now seems to be writing more about that identity: his memories of discomfort in Scouts, with sport, and springing two fellows doing something lewd in a restroom.

''It's happened to me a couple of times where I've been on tour and I've signed books and a woman will have brought her son, and it's a boy, but she's letting the boy live as a girl,'' he says. ''It's made me realise that, hopefully in my lifetime, there won't be anything strange about being gay. There won't be any feelings associated with it of being wrong or being an outcast or worrying that you're the only one in the world.

''But I think about it for myself; I think about it all the time. Hugh and I living here: when I was growing up I longed to live like in the 1920s and '30s, I used to think life was so much better back then, but not if you were gay. Probably Hugh and I couldn't have lived in the same house together. We'd have to invent some kind of story, you know? People would have steered clear of us.

''I mean, I think [my sexuality] definitely informs who I was, just in terms of trying to 'pass' [as straight] … Going to school and watching other boys and then doing what they do. I'm 56 years old. There were no books in my library about homosexuality. There was nobody on TV, no mention of it.

''It was really easy to believe that I was the only one on Earth. Now with the internet and stuff, even if you grow up in a real shithole, in 2013 you're going to be aware you're not the only one.''

In any case, Sedaris doesn't write about sex - ''people would imagine me naked and it's not pretty'' - and, ranging over his writing career, has dealt with his sexuality by demonstrating his relationship with Hamrick is like any other.

In an earlier essay he's mentioned being lost at Taronga Zoo - separated, momentarily, from Hamrick - and in another piece, recounts a phone call between them to subtle emotional effect.

''That was in a story called Old Faithful,'' he says. ''For some reason when I read that story, that's the closest I've ever come to crying on stage.'' He laughs. ''It's so simple: 'Don't hang up'; 'I won't.''' Sedaris takes in a deep breath and there is just the slightest crack in his voice on the line.

''It's interesting to me because I've had gay people come to readings before and say, 'Where are all the gay people?' I've often thought it's because I don't write about sex. You know what I mean?''

Once Sedaris took part in a reading by several authors for a gay magazine called Straight to Hell, about ''real homosexual experiences''. The writer before him read an explicit sex scene - the line is repeated in Sedaris' collection; suffice it to say it involves ''balls'' - and Sedaris roars with laughter at the memory.

Sedaris followed, reading his own piece in the voice of a ''character'' who brushes another man's arm and becomes infatuated. Nothing more. The love goes unrequited. No follow-up is possible.

''It's not like I thought, 'Oh, I don't want to alienate straight people; I am not going to write [explicitly].' It's just not my thing.''

Let's Explore Diabetes with Owls will be published by Little, Brown on April 30, $29.99.