Why don’t trees fall down?

Posted on August 11, 2020 by yamey

SOME YEARS AGO, I was walking in Stoke Common (just north of Slough) with my teacher and close friend, the late Professor Robert Harkness. The Common was a wooded area with a variety of trees. Some of them looked very awkward in that their curved or leaning trunks seemed to defy gravity. Yet, the trees did not fall over despite this.

TREE 3

Robert, who was a renowned physiologist, was also a naturalist. Everything natural aroused his interest. As we walked through the woods, he explained that the trees did not topple over because each of them maintained their own centres of gravity as they grew. These centres of gravity must, he considered change constantly during the long lifetimes of the trees. How, he wondered, did the trees grow in such a way that they never became unbalanced and always remained standing?

He never told me the answer. Maybe, he did not know, but ever since that damp grey afternoon with him on Stoke Common, I always look at trees and wonder whether anyone knows the answer to his question. This afternoon, I was walking along the lovely tree-lined path that leads to Kenwood House from its public car park, when I noticed some trees growing on a steep slope lining it. The trees’ roots seemed to be clinging to the slope, hanging on for dear life. Seeing them reminded me of Robert and his wondering about arboreal ‘assessment’ of centres of balance and a fine old friend, who passed away in June 2006.

The leaning tree

Posted on April 21, 2020 by yamey

LATE 18 leaf

“A PICTURE IS WORTH A THOUSAND WORDS” It is not known exactly when this well-known sentence was first used, but an article in Wikipedia suggests that one of the first times it appeared in print was in an advertisement for a Texan newspaper, the “San Antonio Light”, in 1918. I do not know whether I can write a thousand words to put the attached picture in context, so you will have to make do with what I am able muster.

Just over a year ago, my wife and I were ‘wintering’ in India. We left our daughter looking after our flat in Kensington. One day, she sent us a message informing us that one of the old trees in our street had toppled over in the middle of the night.

The tree that fell always looked precarious as its trunk leaned over the road at quite a sharp angle, making it tricky to park a car next to it. A neighbour told us that it had done so for well over a century. His evidence was that the very same tree can be seen leaning over the road in an old photograph of our street taken about 150 years ago. So, the tree was not inherently unstable.

Many years ago, while walking through woods with my old PhD supervisor (and by then a close friend), he pointed out the variety of shapes and inclinations of the tree trunks around us. He wondered how a tree ‘knew’ how to grow in various directions whilst maintaining a centre of gravity that stopped it toppling over. Clearly, our late lamented leaning tree ‘knew what it was doing as it had been leaning seemingly precariously for at least a century and a half.

After we returned from India, there was a bare patch where the tree had stood for so long. A neighbour, who makes it his business to find out in detail what happens in our small street told us what befell our tree. The local council decided to move the position of the curb and so to widen the pavement around the tree, the idea being to narrow the road at that point and thereby prevent parking next to the tree.

Unfortunately, the workmen assigned to carry out this job managed to cut through part of the tree’s root system. This destabilised the tree, which then fell over across the street. While falling, the tree damaged a first-floor balustrade and terrace on a building across the street. Luckily, there were no human casualties.

For some months, the site of the fallen tree remained treeless. Then, a small tree with a slender trunk, a sapling, was planted by the council. Day by day, we watched it producing leaves. These changed colour in the autumn, looked sickly, and fell off, leaving a sad looking spindly tree. Then, we spent another winter in India.

When we returned in late February this year (2020), the young tree was still standing and still looking lifeless. As the weeks passed, we were very pleased to see buds forming on its slender branches. These buds have grown in size and are, at last, unfurling to reveal the tiny leaves seen in the photograph.

It is pleasing to see that even in these troubled times, nature has something positive to lift our spirits.

Well, I have reached about 580 words, not quite a thousand. However, as the saying goes, I hope my photo is worth at least a thousand words and is something to enjoy.