To 'espalier' (pronounced 'es pal yay') a tree refers to the practice of controlling woody plant growth for the production of fruit through pruning and tying branches to a frame or a wired support. It is often done in a formal style, and it is meant to be such that the tree would sit flat against a structure such as a wall, fence, or trellis.
In addition to their aesthetic appeal, they are also useful for gardens in which space is limited, or where they can be planted adjacent to a wall that can reflect more sunlight and retain heat overnight to allow the season to be extended and ultimately so that fruit has more time to mature. Having said that, there is a fair bit of pruning work involved in maintaining the form.
Recently we had been asked to source some of these rare and hard to find trees, and we thought you might like to see one. This large one that is being held by our lovely Linda Schlueter is of Lodi Apple, but smaller ones that are 'multi-grafts' (with more than one type of apple on one tree) are also available this year too. The best part of these trees is that the hardest part of espalier (getting the initial training done) has already been done.