Bloody biodiversity. Don’t you hate it? Just when you think you’ve got half an idea of what’s going on, you find there are a whole load of other things you had no idea about. Last week I wrote about blackthorn, the celebrated early blossomer of the English hedgerow. Every word of it was true, save my reason for writing it.

Because, I learn, what I saw was not blackthorn at all. It was the closely related cherry plum. This is an import from Persia, the chief ancestor of all cultivated plums, barely recognised, I am told, but very common in British hedgerows. Leaves appear almost simultaneously with the blossom: but when the true blackthorn bursts into flower at the end of this month, it will be weeks before the leaves appear. The cherry plum doesn’t often bear fruit in this country, but it did in abundance last autumn. I thought the fruit were sloes, and that therefore the trees were blackthorn.

I am a little bit richer for that mistake, for the reminder that, once again, there are more species than I knew about, a reminder that, once again, there are more species than I will ever know about.

Ignorance is as important as knowledge when you seek to understand the wild world. Does it matter that I was unable to tell blackthorn from cherry plum, and that now I can? John Fowles, author of The French Lieutenant’s Woman, was a great nature man. He once wrote: “Any trained biologist will tell you that identification expertise has about as much relation to serious biology as knowing national flags has to do with being an expert on international affairs.”

Fowles loathed the minutiae of identification; hated the idea that the wild world was a competition with no prizes — your skill against the endlessly baffling challenges of nature. He saw the naming of things as just another form of hunting, of possessing, of overwhelming. Yes, yes, indeed: but surely, knowing anybody’s name is the first step towards intimacy.

Expertise is not a basic requirement, however: and as someone who has written books about being a bad birdwatcher, I have a right to speak. People cut themselves off from the wild world with the belief that you must either be an expert or nothing. No. The most important thing, for biologist, poet or dog-walker, is pleasure: that essential understanding that the wild is part of you and you are part of it.

Then, perhaps, a name; and with it, a little caress of added intimacy.

And this week, from the top of a small line of pines — to be accurate, they were Norway spruces, or Christmas trees, you can decide yourself whether or not that matters — a thin, high little song, the first time I had heard it this year. And yes, I have got this one right. I suspect I would be better at identifying trees if only they would sing.

It was a goldcrest: Britain’s smallest bird, four of them to the ounce. The piercing, sibilant tumbling of notes added lustre to an already bright winter morning. The daily addition of spring to winter’s regress is one of the great wild pleasures of life: and here was the tiny goldcrest hastening the turning of the year. Listen under pine trees on the next bright morning: you have a good chance of hearing one yourself. But the song is so very high that it may, like bats and dog whistles, be beyond your range. High notes are the first thing to go: a celebrated ornithologist once remarked that he could no longer hear goldcrests or women.

Lord knows, I am the last person to go on about identification skills, since my own are so limited. But such knowledge as I have enriches my life. It was not just a bit of national flag-spotting when I picked out the song of the goldcrest from the rest — three species of finch, robin, song thrush and mistle thrush all giving it their best. It was a tiny — four to the ounce — but significant advance in the advance of spring into the enemy territory of winter, and I was the richer, not because I had got the better of nature, but because I was more closely aligned with nature.

And with my ignorance of cherry plums comes, once again, that wonderful, heady feeling about biodiversity: the certainty that I will never get the better of it; that this is a competition I will always lose; and that life is a great deal the richer for that fact. For this endless diversity is not something freakish and bizarre and quirky. It is nothing less than the basic mechanism of life.

A small failure of identification skills provides a sudden, sharp understanding of the way the planet works.

Times Recommends

• Bank charges hit us for being human
• Sorry, Father, thou still shalt not steal
• The shed where Santa’s failures go to die