I HAVE been to London. Not a big thing to announce you might think.

I used to go regularly and zip up and down the underground.

These days it’s a lot more effort to travel there and, to tell the truth, I feel more like Country Mouse than Town Mouse.

I like the countryside and all that it offers us –I like the seasons and the animals and plants here – but I had promised myself that I would visit the Royal Opera House at least once in my life and so I planned the trip.

They say that there is wildlife in the city, and I am sure that there is, but I didn’t see any wild animals. Mind you, these days I get a cab from door to door, so I probably missed what people who live there can see.

I did see the London plane tree, though. They are everywhere in the city.

They have been growing there for hundreds of years.

They have a special survival technique which helps them live and survive in polluted towns and cities.

They have special bark.

If you look at the tree trunks you can clearly see several colours.

Some parts are darker, and others shade through to cream.

This is because the London plane sheds its bark regularly in flakes.

In industrial London the tree trunks would be black with soot and other waste.

The poisons could damage the trunk which protects the tree, but the plane tree has solved this problem.

At any one time much of the bark will be renewed and clean.

Pollution would not be on the tree.

Even today, it is a good survival technique, as emissions from cars and buses could damage the trees’ bark if they did not have this clever trick.

I once saw a peppered moth in London with a clever trick, too.

It was on a plane tree trunk and it was so camouflaged you had to stare to be sure it was there. A little boy saw me looking and came to watch.

“What are you looking at?” he asked.

I pointed to the hardly visible pale moth sitting still.

The boy ran to fetch his dad and we all marvelled.

But the story continues because this species of moth used to be black in London, when the trees were stained with soot. Birds couldn’t see it, so it survived.

Now tree trunks are much cleaner, a white form of the same moth species is more prevalent. The black form is hardly ever seen now.

Wildlife develops ways of surviving our progress.

“Bravo” shouted the big lady in a pink silk dress, sitting next to me at the opera.

The singers had done so well – and being a country mouse, I thought of the tree and the moth and how well they had done, too.

We caught the train home from Euston where the famous red buses come and go.

I took my photo of the tree with its mottled bark. And now there is another threat. High Speed 2 is starting at Euston, demolition work has begun already.

My tree could be in the way of our new fast trains.

If someone saves it, I think that would be true progress. Then I can shout ‘Bravo’.