Arborists prepare to cringe. I am a huge fan of the effects created by two pruning techniques, pleaching and pollarding. Both of these techniques are used widely in Europe; but even there I sense there relevance is seemingly fading. For me they combine two of the most essential garden tenants I know of, form and sculpture.
Pleaching is the act of pruning the canopy of a tree up and providing a consistent height while also containing the growth on the sides and top of the plant. This is often done with single stem trees but can also be done with multi-stem plants(see my last posting on the Ware’s garden, the trees against the wall are pleached Carpinus betulus fastigiata). The results are marvelous. Perfect for creating a screen or accentuating a site line with and allee.
Pollarding is seen even less often. It is a much more difficult technique to properly perform. Basically what you are doing is constraining the height and ultimate size of a tree. I would say this all came about when someone planted a tree that began to get much to large for the space where it was installed. In an attempt to keep the tree in check they started pruning away. The results are a tree that is kept much smaller that its natural tendencies would allow. As you can see in the picture the results with foliage in place are great; but the real sculptural presence comes into play when the leaves drop and you are left with the knobby clubs at the end of the branches. So lets remember to look to our Garden Design History for ideas and inspiration and not forget the techniques used in the past.