I could speak to you today about pine and plane and sycamore and larch, but instead I wish to focus your attention upon ash and box and elm and yew. Ash. Box. Elm. Yew. Four trees in alphabetical order. It is not necessarily the best order in which to arrange trees, certainly not if one were planting an orchard, but for our present purposes it will do, it will do. Each is a three-letter word for a tree, each has a trunk and leafage and, of course, roots. These are not the roots of which Alex Haley wrote, but gnarled and twisting roots which anchor the ash or the box or the elm or the yew in place, wherever that place may be. It is the presence of roots, under the tree, submerged in the muck, that account for your inability to push the tree over with one mighty heave.

So when we consider the ash and the box and the elm and the yew we must keep in the forefront of our minds that they are rooted, anchored, not easily toppled. This helps us to tell them apart from toppleable things, which are countless. There are more things in the world that topple over than do not. I would have you take a few moments to think about that.

You, for example, are the sort of thing that could be toppled, while standing there lost in thought. You might be knocked over by a ferociously high wind, shoved by a shover, or suffer from a sudden and catastrophic weakness at the knees. In certain circumstances, the same is indeed true of ash and box and elm and yew. High winds have toppled trees, shovers armed with chainsaws have toppled them, even weakness in a tree-trunk, caused by blight or disease, can topple a tree. The point I am making is that it is much easier to topple you than it is to topple a tree. Unlike a tree, you are not rooted to the ground, at least not in your natural state.

Do not confuse the homophones you and yew, by the way.

It is not just trees with three-letter names that require might and main to topple them. The aforementioned pine and plane and sycamore and larch are also firmly rooted. The reason they do not concern us today is that their names contain more than three letters. When dealing with a subject as wide-ranging and breathtaking and complicated as trees, we have to focus our attentions more narrowly if we are to get anywhere, at least in the short term. Only those with the most fanatical interest will go the whole hog and devote the best part of their lives to the study of trees. The rest of us must make do with partial, limited knowledge. We will wish to be sufficiently familiar with certain types of tree so that we can hold our own in a tree-based conversation.

For example, we might be at a swish and sophisticated cocktail party and be buttonholed by a person who, to break the ice, says something regarding trees.

“It is interesting you should say that,” we can reply, winningly, “For just the other day I read a piece about the ash and the box and the elm and the yew.”

“Oh really?” says our interlocutor, and before we know it the two of us are babbling away nineteen to the dozen and getting on like a house on fire. Such social success is always rewarding. Had we not had a ready reply, we might have been left flailing and dimwitted, clutching our cocktail glass and flushing with discomfort.

It is not overwhelmingly important to be able to tell an ash from a box or an elm from a yew or a box from an elm or a yew from an ash or a box from a yew or an ash from an elm. If you can do so, all well and good, but depending on the company at the cocktail party you are attending you might want to keep that knowledge under your hat. If you begin to prattle on in detail about the trees and their characteristics you might be taken for a fanatic with no interest in, or knowledge of, any other topic. Nobody wants to get stuck next to a monomaniac at a cocktail party.

Conversely, if you are the one who finds yourself trapped with a tree-fanatical nutcase, intent on describing to you in brain-numbing detail the ash and the box and the elm and the yew, you can always topple over. They will interpret this as a swoon, and call for smelling salts and perhaps a snifter of brandy. You can then sit up and rub your head and look disconcerted. You might be ushered outside for a spot of fresh air, and if the party is taking place in a rustic location, there could be a coppice or spinney nearby. But in your fragile state, or let us say your pretence of a fragile state, nobody, not even the nutcase, will call on you to identify the trees, which may or may not include the ash, the box, the elm, the yew.