Michael McCarthy: Kew basks in the return of winter

Nature Notebook

Children love snow, of course. But at the height of the recent white-out, when the unaccustomed blizzard had closed schools and stopped all London buses and trapped motorists in their cars at the sides of motorways, I met a grown-up who was also rubbing his hands in glee.

He was Tony Kirkham, the head of the arboretum at the Royal Botanic Gardens, Kew. Tony is the man who is actually in charge of the gardens at Kew Gardens, and he was delighted with the thick white blanket – nine inches of the stuff – which had been deposited over the 300 acres in his care.

Certainly, the fresh powder snow made Kew look wonderful, transforming what are anyway noble landscapes into vistas of an almost dream-like loveliness. But it wasn't the look of things that had made Tony so pleased when I wandered into his office. It was what it was doing for the trees, shrubs and plants all about us.

Firstly, he pointed out, for several years Kew had been experiencing drought conditions, and even the rains of the past two summers had not brought the soil moisture level up to what the trees required. But the heavy snow blanket, as it melted, would help to do that. Secondly, it might help to kill off some recent pests whose larvae overwintered in the leaf litter, not least the horse chestnut leaf miner moth, which came into Britain in 2002 from Macedonia and now wrecks the leaves of all the conker trees in Kew and a large belt of south and west London, from midsummer on. Thirdly, it would give everything a rest. Recent very mild winters and early springs have seen the seasons virtually merging, resulting in a longer growing period which puts the trees under stress. But the snow meant that "everything is shut down asleep and not even thinking about waking up". Tony said: "I'm delighted." May he be blessed with more snow in the future; but don't bank on it. It was a small but telling insight into what some of the consequences may be if climate change does away with old-fashioned winters altogether.

A green day on the feeder

Many of our garden birds – blue tits, great tits, goldfinches – seem to have vanished with the snow. Have they died? Have they gone elsewhere in search of food? However, they have been replaced on the feeder by two occasional but splendid visitors: a pair of siskins. These pine-forest finches look better in life than they do in the bird guides (usually it's the other way round). They look glowing green. The children exclaim: "What are those green birds!?"