When clipping an old tree that is a perfectly square one, it is a good practice to use either a line or some kind of straight edge. If the man who is doing the work uses one or the other he can generally give the tree a better and more finished appearance than if he trusts to the eye only.
Perhaps of all the different kind of shapes there are to clip in the Topiary garden, hedges require the most skill and care, and only the most experienced men should be allowed to undertake the work of clipping them. Hedges in the garden are mostly planted in such a way that their entire length is visible, and of course the most casual observer can see at a glance whether they are properly clipped or if there are any shear marks visible on them. If the hedge is composed mostly of curves, then of course the clipping is not such a difficult matter. A long, straight hedge and one that is almost entirely made up of curves, differ in the same respect with regard to the ease with which they can be clipped, exactly in the same way as a round or an oval tree. When clipping a straight hedge a person should never trust entirely to the eye, and lines should always be used; and for the purpose nothing is better than ordinary garden lines.
OLD EXAMPLE OF TOPIARY IN BOX AT COMPTON WYNYATES ]
In the case of hedges that are cut into battlements at the top, these should have a line stretched lengthways along the ground, another along the base of the battlements, and another along the top of the battlements; and whatever size and width the battlements are, say, for instance, two feet high and two feet in width between them, a stick cut exactly two feet in length or a two-foot rule should be used to measure the exact height and distance between the battlements; and if those precautions are taken, any person with a fair knowledge of the art of clipping can hardly with ordinary care and attention get wrong; as, after all, the work of clipping Topiary trees is not so difficult as might be expected.
There are several points that should always be remembered. Symmetry and shape are necessary to make a good tree; and this may be said to be the first and most important factor in the work. Another point is to take particular care that the shears do not cut off more than is necessary. By that I mean, never to allow the shears to cut deep enough into the tree to make a hole. Another very important point to aim at is to give the tree as smooth and even an appearance as possible after the work is finished. I am perfectly aware that, in a large collection of yews or other clipped trees, there are always some that it is impossible to clip properly, on account of weak growth, or some other cause. For instance, trees that are growing in a part of the garden where they are fully exposed to wind and storm are almost certain to get into an unhealthy condition. The growth becomes weak and stunted, or perhaps the branches get worked out of place, or even die out altogether. In the case of trees of that description, no matter how much tying is done or how carefully they are clipped, they can never be made to have the same appearance as those that are full of young growth and are in a healthy and vigorous state.