I think it's all down to melancholy. If you try and work out what the special attraction of autumn is, I think that, ultimately, you come up with a mood.
Melancholy can mean outright depression or dejection, but the word does have a range of overtones and what I mean in the context of September, October and November, and how we feel about the period, is a sort of sadness which is not entirely unwelcome; a sort of sober, slowing-down of the spirit, leaving us much given to reflection.
Of course, for some people autumn won't mean a thing other than the boring fact that it's not summer any more, and they might see it as merely an intense work or school interlude between the beach and Christmas, with longer nights and worsening weather; or maybe the time when the football season starts to get serious.
But for anyone capable of looking up from their screen, for anyone in the slightest way alive to the rhythms of the natural world and its sights and sounds and smells, autumn has a peculiar personality of its own which is powerfully attractive.
Most obviously, the world rebeautifies itself: the autumn foliage becomes resplendent. I've never heard anyone remark on quite how curious this phenomenon is, in biological terms, given everything negative we know about ageing.
The leaves of trees are welcome and wonderful in their green iridescence when they burst out in April, but by June their bloom is gone, and by August they're plain dull. With most life forms, that would be it. We could expect no more. Instead, by a pure accident of organic chemistry, leaves are reborn, as they start to die, in an astonishing range of colours that puts their spring birth to shame.
It's as if they have another spring in another palette, the second one even more vibrant than the first: terracotta, russet, bronze, purple, gold. Even that subtlest of shades, old gold – gold with a burnished look, gold with a tiny hint of red, almost the quintessential autumn colour (look at Stourhead in Wiltshire, pictured opposite).
And this is decay. This is the winding-down of everything, towards death. Yet the great gift of autumn is that the beginning of the end doesn't feel like decay, at least on the surface, it doesn't feel like a crumbling and a rottening and a collapse from within; it feels like the arrival of a world of new sensations.
The first one is mist. To me, autumn mist is something you smell before you see it; it's the initial hint of a tang on the air as you leave the house in the morning, just creeping into the nostrils, and you know in your tissues at once that summer is over and the world is turning; then you notice that the sunshine is hazy. I've sensed it as early as the last week of August, but I would guess it's mainly a feature of September.
The next one's smoke. This is another tang that drifts to the nostrils after the summer, the smoke of wood fires (and coal fires in the past), the smoke of bonfires; you start to smell that in October, and see it hanging in the air on still days of high pressure. A third one is frost: different again. Not just a whitening, but a hardening and a sharpening of everything, yet welcome, when it first arrives, with the pleasant surprise of novelty.
Mist, smoke and frost; yet so much more. Tastes: the earthy taste of mushrooms; the rich soft crumble of roasted chestnuts; the dark pungency of game; the resinous bite of juniper berries. Sounds: the swishing of kicked leaves and their crunch underfoot; the roar of a gale; the metallic cough of a pheasant echoing through the woodlands. Sights: the foliage, of course, in all its glory, but less obvious things: the softening of the sunlight; the faded blue of harebells; the reddening of ripening apples; the understated dun shades of chrysanthemums.
All of this is gladdening, a source of the most enormous pleasure, but would you not agree that it doesn't quite lift the heart the way spring flowers or birdsong do?
For bluebells and birdsong have hope about them, a promise of what's to come, whereas the signs of autumn, for all their splendour, are the signs of a world that is dying; and there's no escaping that.
There's where the melancholy comes from: the subtext, the underlying, insistent theme beneath the year's last burst of beauty is that this is only occurring because the end is not far off, the end that comes to all living things, including us. If we look, in the autumn foliage we can see our own mortality: a beauty with a sadness never far away.
This has never been better expressed than by Gerard Manley Hopkins, the tortured Victorian Jesuit who wrote the 19th century's most singular poems in English. In a short and exquisite lyric, "Spring and Fall", he addresses a young girl, Margaret, who, he is astonished to find, is crying over the falling of the autumn leaves.
With great tenderness he tells her that as she grows up she may be much less concerned about leaves and more concerned about other mortality; but he marvels at whatever it is in her young spirit that has already sensed that what she is seeing in the falling leaves, prefigures what will one day come to her too:
It is the blight man was born for.
It is Margaret you mourn for.
Spring and fall, to a young child
Margaret, are you grieving
Over Goldengrove unleaving?
Leaves, like the things of man, you
With your fresh thoughts care for, can you?
Ah! as the heart grows older
It will come to such sights colder
By and by, nor spare a sigh
Though worlds of wanwood leafmeal lie;
And yet you will weep and now why.
Now no matter, child, the name:
Sorrow's springs are the same.
Nor mouth had, no nor mind, expressed
What heart heard of, ghost guessed:
It is the blight man was born for,
It is Margaret you mourn for.
Gerard Manley Hopkins
The Ten Best Things to do this autumn
1. Be a leaf-peeper
Make a special trip to see the autumn foliage, just like the leaf-peeping Americans who support a whole tourist industry in New England. The trees are at their best now; in fact, they're even starting to go over, so hurry.
2. Drink Beaujolais Nouveau
Yes, it's a gimmick. Yes, it's been completely out of fashion for a decade. But when the new Beaujolais is released on the third Thursday of November (the 18th this year) it can be a pleasure to drink. Stick it in the fridge for 20 minutes first.
3. Take part in schoolboy football
There's nothing so invigorating as a crisp autumn morning on the recreation ground when your lad and his 11-year-old pals line up against the team from the next suburb. (It's less invigorating when the boy your son tackles a little too sharply turns out to have a dad with a tattooed face.)
4. Gather ye mushrooms
Autumn is the time for wild mushrooms, so go down to the woods now to find those great prizes, chanterelles and ceps. You can also find death caps and destroying angels, which will kill you. So take an expert (Google "fungal forays").
5. Hunt the wryneck
This curious brown woodpecker which can turn its head through nearly 360 degrees is more or less extinct in Britain, but migrating individuals from Scandinavia turn up every autumn on the East Coast. Treat yourself to a birding weekend in North Norfolk to find one.
6. Eat game
Pheasants and venison and suchlike are in the shops now. Some people might have a problem with hunting, but others take the view that they would much rather eat meat that's never been near a slaughterhouse.
7. Watch wild geese and wild swans
The great wildlife spectacles of the autumn are the skeins of wild geese and swans which fly here from places as far apart as Greenland and Siberia. Look up the Wildfowl and Wetlands Trust website to find out where to see these birds.
8. Risottos and autumn vegetables
Pumpkins, aubergines, mushrooms, savoy cabbage, even carrots, seem great at this time of year. So do risottos. Who knows why? They just do.
9. A walk with a log fire at the end of it
As the autumn days get colder and darker, it's a real treat to walk out from a pub or hotel and walk back to its roaring fire.
10. Plan your next summer holiday
By the end of November, most of what autumn has to offer is over: the trees are leafless black boughs and the weather is usually wet and horrible. You might as well start dreaming of that villa in Cephalonia.
Enter our photo competition
How are the autumn colours looking in your part of the woods? Have you seen been inspired to get out your camera by the sight of some truly fabulous foliage?
Send us your pictures and a few words about where and when they were taken and we'll print the best ones. We'll send those whose entries are published a bottle of Beaujolais Nouveau.
Both this year and last year have been good for leaf colour in the UK. This year, it's down to the the long drought in the spring and the wet, cool late summer that followed. The result is an autumn display that ranges from the yellow of birches through the orange of rowans to the deep reds of Japanese maples. Try to visit the gardens famous for their trees, such as Westonbirt Arboretum in Gloucestershire, left, or Sheffield Park in East Sussex.
Your picture doesn't have to be of a posh garden, however. Your own backyard may be just as flamboyant. Email entries to firstname.lastname@example.org. Pictures should be in jpeg format and 300dpi (5-6MB). Remember to include your name and address.