Trees are generally single-stemmed woody plants growing from up to 80 metres tall. They are used to create shade, screen unsightly objects and frame views. They can be planted singly, in groves or even as lines to form avenues or screens. Many trees can be pruned to create hedges, pleaches or espaliers so that even the smallest garden can make use of trees. Evergreen trees can either be broadleaved such as Magnolia grandiflora or more commonly coniferous such as Cedars and Pine trees. Aside from their structural benefits, trees are invaluable for wildlife adding an extra dimension to the ecosystem as well as flowers, berries, foliage, bark and autumn colour.
Care of trees usually involves staking and formative training in the early years. Tree ties need to be loosened as the trunk expands and it can be as much as 3 years before the roots are adequately grown so that watering in dry spells is no longer required. Unwanted branches and growth should be removed as soon as possible with trees so that the cuts heal and growth is concentrated in the desired way. Most trees are best pruned in winter when they are dormant and the structure can be seen. In this way, damaged, diseased and crossing/rubbing branches can be identified and cut out. However, some trees such as cherries, plums and walnuts are best pruned in summer to avoid specific diseases which can enter winter pruning cuts.